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Category Archives: Blog

October 17, 2025
October 17, 2025

New Light-Based Cancer Therapy

Article Summary—summarize current event article of a specific type of cancer treatment or medication.

Instructions:

Prepare a written response to the prompt using a word processor. Please save your file in .doc or .docx format. Your response should be complete and should comply with APA writing requirements.

*Students are encouraged to visit the following website before completing writing assignments. Purdue Online Writing Lab (OWL):  https://owl.purdue.edu/owl/purdue_owl.htmlLinks to an external site.

· Find a current event article ( not webpage definition, Wikipedia, WebMD, etc.) published within the last year related to a specific type of cancer treatment

· Write a 1-page summary (double spaced, 12 pt font) demonstrating your understanding of the article in your own words New Light-Based Cancer Therapy

New Light-Based Cancer Therapy

  • What is the new light-based cancer therapy and how does it work?,

  • Which cancers or tissues did the researchers target?,

  • What advantages does this therapy claim over traditional treatments?,

  • What limitations or challenges are noted?,

  • What is the significance of this innovation for future cancer treatment?


Summary of the Article

A recent article describes an innovative light-based cancer therapy that leverages near-infrared LED light and tin-based nanoflakes (SnOx) to selectively destroy tumor cells while sparing healthy tissue. The nanoflakes absorb the LED light and convert it into localized heat, inducing thermal damage to cancerous cells without affecting surrounding normal cells. This noninvasive method aims to reduce the collateral damage common in chemotherapy or radiation therapy. Researchers tested this approach in laboratory and preclinical models, showing effective tumor shrinkage and minimal side effects, thanks to the spatial targeting of the therapy.

The therapy was evaluated on tumors in animal studies, and the results suggest that more accessible, low-cost LED sources (rather than expensive lasers) might make this treatment more broadly available. One major advantage is precision: since only cells that take up the nanomaterials are heated, healthy tissues are largely preserved. It is also potentially safer and less invasive, possibly allowing outpatient or even home-based treatments in the future.

However, the article notes challenges: delivering nanoflakes uniformly to the tumor, ensuring adequate penetration of LED light in deeper tissues, controlling heat spread, and validating safety and efficacy in human clinical trials. Translating from animal models to humans always carries uncertainty. Long-term toxicity, biodistribution of nanomaterials, and regulatory hurdles remain.

The significance of this therapy lies in its potential to transform cancer treatment by providing a gentler, more targeted alternative to conventional modalities. If successful in clinical translation, it could reduce side effects, improve patient quality of life, and expand access to treatment in resource-limited settings. It also reflects the trend toward theranostics—combining therapy with diagnostic targeting—and precision oncology, where treatments are more tailored to tumor biology and microenvironment.


References
“New light-based cancer therapy kills tumour cells without harming healthy tissue.” Times of India, 2025.
Cancer.gov. (2025). Experimental Treatment Uses Engineered Fat Cells to “Starve” Tumors. Retrieved from https://www.cancer.gov/news-events/cancer-currents-blog
Experts Forecast Cancer Research and Treatment Advances in 2025. (2025). American Association for Cancer Research.

October 17, 2025
October 17, 2025

Interagency Collaboration in Law Enforcement

1. Select your case study topic from the following options:

  • Interagency Collaboration in Law Enforcement:
    • Analyze a police-led initiative that collaborates with social  services (e.g., Crisis Intervention teams, co-responder models) to  address mental health crises, substance abuse, or homelessness.
    • Evaluate the administrative structures that support or hinder the partnership and its impact.
  • Court-Based Social Service Integration:
    • Examine a problem-solving court that integrates social services into judicial processes.
    • Analyze how court administrators balance case flow efficiency with the delivery of rehabilitative services.
  • Corrections and Reentry Programs:
    • Focus on a reentry initiative that bridges corrections and community service.
    • Evaluate how correctional administrators collaborate with external organizations to support reintegration and reduce recidivism.Interagency Collaboration in Law Enforcement
  • Victim Services and Community Partnerships:
    • Assess a program that integrates victim advocacy services into criminal justice processes.
    • Explore how criminal justice agencies coordinate with community partners to enhance victim support and rights

2. Post  your draft executive summary providing a concise overview of the case  study, its significance, and key issues related to interagency  collaboration and social service integration. You must use a minimum of  three (3) peer-reviewed sources.  APA 7 format is required.Interagency Collaboration in Law Enforcement

  • Analyze a police-led initiative that collaborates with social services to address mental health crises substance abuse or homelessness,

  • Evaluate the administrative structures that support or hinder the partnership and its impact,

  • Provide a concise overview of the case study and its significance,

  • Identify key issues related to interagency collaboration and social service integration,

  • Use at least three peer-reviewed sources in APA 7 format.


Executive Summary

This case study examines Crisis Intervention Teams (CIT), a police-led initiative designed to foster collaboration between law enforcement agencies and social service providers in addressing incidents involving individuals with mental health issues, substance abuse disorders, or homelessness. The CIT model, first developed in Memphis, Tennessee, exemplifies effective interagency collaboration by combining law enforcement, mental health professionals, and community advocates to promote crisis de-escalation and diversion from the criminal justice system toward appropriate treatment services.

The significance of this collaboration lies in its potential to reduce use-of-force incidents, recidivism, and incarceration rates among vulnerable populations. Administratively, the success of CIT programs depends on strong cross-sector coordination, joint training, and shared funding mechanisms. Supportive structures include clear communication protocols, memoranda of understanding (MOUs), and regular interagency meetings. However, challenges persist due to bureaucratic barriers, inconsistent funding, and differing agency priorities.

Key issues in interagency collaboration include aligning organizational cultures, maintaining consistent information sharing, and ensuring that both law enforcement and social service providers receive adequate training. The integration of social services into police work requires adaptive leadership, community trust, and evidence-based evaluation.

Overall, the CIT model demonstrates that interagency collaboration enhances both public safety and community well-being by addressing the root causes of crisis situations rather than relying solely on punitive measures. Continued investment in these partnerships is crucial for developing comprehensive, humane responses to complex social problems.


References (APA 7th Edition):

Compton, M. T., Bahora, M., Watson, A. C., & Oliva, J. R. (2008). A comprehensive review of Crisis Intervention Team (CIT) programs. Journal of the American Academy of Psychiatry and the Law, 36(1), 47–55.

Watson, A. C., & Fulambarker, A. J. (2012). The Crisis Intervention Team model of police response to mental health crises: A primer for mental health practitioners.

October 17, 2025
October 17, 2025

Enzyme Activity Experiment

In this lab, you will use common household materials to set up an experiment demonstrating how enzymes work.

Make sure that you have on hand all of the items from the week’s shopping list before you begin. You will need several hours or overnight to complete this lab, so make sure that you allow enough time.

  • Open the attached file to read the procedure for the lab.
  • Download and save the file.
  • Follow all the instructions carefully, answer all the questions, and include a picture of the experiment.
  • Submission Method: Answer in the attached file and submit as a .docx file.

Enzyme Activity Experiment

  • What materials are needed for the enzyme experiment?,

  • What is the procedure for setting up the experiment?,

  • What observations were made during the experiment?,

  • What conclusions can be drawn about enzyme function?,

  • How does temperature or time affect enzyme activity?


Comprehensive General Answer:

1. Materials Needed
For this enzyme lab, gather common household materials such as:

  • Fresh pineapple (or other fruit containing natural enzymes like kiwi or papaya)

  • Gelatin powder

  • Measuring cups and spoons

  • Bowls or cups

  • Hot water

  • Refrigerator

  • Optional: canned pineapple (for comparison), timer, and thermometer


2. Procedure Overview

  1. Prepare the gelatin mixture according to the instructions on the packet using hot water. Pour equal amounts into several cups.

  2. Label each cup for the condition being tested:

    • Control (plain gelatin)

    • Fresh pineapple

    • Canned pineapple

    • (Optional) Cooked pineapple or frozen pineapple

  3. Add the fruit to each gelatin cup (except the control). Use the same amount of fruit in each sample.

  4. Refrigerate the samples for several hours or overnight.

  5. Observe the results: note which gelatin solidifies and which remains liquid.

  6. Record your findings and take a photo of the samples showing the difference in consistency.


3. Observations

  • The control sample (plain gelatin) should solidify normally.

  • The canned pineapple sample should also solidify because the fruit has been heat-treated during canning, which denatures the enzymes.

  • The fresh pineapple sample typically remains liquid because bromelain, a natural enzyme found in fresh pineapple, breaks down proteins in the gelatin, preventing it from setting.


4. Conclusion
This experiment demonstrates how enzymes act as biological catalysts that speed up chemical reactions—in this case, the breakdown of protein molecules in gelatin. The fresh pineapple contains active bromelain enzymes that digest the gelatin proteins, preventing the mixture from solidifying. Heating or processing the fruit destroys the enzyme’s structure (a process known as denaturation), making the canned pineapple ineffective at breaking down the gelatin.


5. Effect of Temperature and Time
Temperature and time play crucial roles in enzyme activity. High heat denatures enzymes, rendering them inactive. Cooler conditions, on the other hand, slow down enzyme reactions, while moderate warmth may increase reaction speed up to a point. Over time, enzyme activity continues until either the substrate (gelatin protein) is fully broken down or the enzyme becomes inactive.


Summary:
This household enzyme lab effectively shows how enzymes function, react to temperature, and influence chemical processes in everyday substances. Fresh pineapple’s active bromelain breaks down gelatin, while canned pineapple—whose enzymes are heat-denatured—does not.

Suggested Image:
Include a labeled photo of the three gelatin samples (Control, Fresh Pineapple, Canned Pineapple) showing the differences in solidification.

October 16, 2025
October 16, 2025

Cilantro vs persley There’s often confusion between these two wonderful culinary herbs, for both cooks and gardeners. Cilantro and flat-leaf parsley have similar uses and are practically twins of each other, visually, but they do have distinct di�erences. This article clarifies their individual characteristics, including their growth habits.

It’s a good day on the blog when I get to talk about two of my favorite, most useful, fresh herbs: cilantro and parsley. As a cooking educator, I often get questions about when to use which. And in the garden, there are often assumptions that they grow similarly to each other, which is not quite the case.

A couple of notes before we get started. In the U.S., we refer to the green leaves of cilantro as cilantro, while in Europe and India they’re called

Cilantro vs Parsley

 

coriander. In the U.S., coriander are the seeds of the cilantro plant.

There are two main types of parsley: flat-leaf (or Italian) and curly. Flat-leaf parsley has a strong, herbal, grassy flavor. Curly parsley, on the other hand, is mild in flavor and papery in texture and is usually used just as a garnish. All references to “parsley” in this article will be referencing flat- leaf parsley.

Now, let’s get to the deets!

Botanical Overview

Cilantro (Coriandrum sativum) — Cilantro (formerly known as Chinese parsley) is a member of the Apiaceae family, and is actually related to parsley. Not surprisingly, given their appearance.

Parsley (Petroselinum crispum) — As noted above, parsley is related to cilantro and is also a member of the Apiaceae family, which includes carrots, fennel, chervil, dill, cumin, lovage, celery, parsnips, Queen Anne’s lace, and more.

Some members of this family — including parsley, dill, carrots, and parsnips — have interesting blooming habits, where the seed-producing flowers are huge, showy, umbrella-like structures, known as umbels, with tiny yellow or white flowers.

Flavor

Cilantro: Also known as coriander in Europe and India, cilantro has a distinct, pungent flavor often described as fresh, citrusy, and slightly peppery. Most people have a love/hate relationship with cilantro because of the presence of aldehydes, which some perceive as a soapy or metallic flavor. But for those of us where cilantro doesn’t taste like soap, it’s a much beloved herb that’s crucial in salsas and guacamole.

Parsley: Flat-leaf parsley has a more robust flavor, described as fresh, slightly bitter, grassy and earthy with pepper undertones, making it suitable for a variety of dishes, especially within Italian cuisine.

 

 

Plant Life Cycle

Cilantro: Cilantro is an annual plant, meaning it completes its life cycle — grows from seed, produces leaves, and then flowers to produce seeds — in one growing season, and does not survive from one year to another.

Cilantro is distinctly a cool-weather plant and will bolt (go to seed) as soon as the weather turns hot. This, of course, is a real bummer for salsa lovers, as cilantro’s growing season does not overlap with onions, tomatoes, and peppers.

Cilantro is easy to grow from seed, and also easily produces seed. When the plant produces flowers, leave it be, and you’ll see seeds appear soon enough. Interestingly, the young, tender, bright green seeds are edible and delicious — pick a few for a treat in your green salads.

 

 

Mature seeds will dry out to brown, and can be ground into the spice known as coriander, or saved to replant next year.

Parsley: Parsley, like many other species in the Apiaceae family, including carrots, is actually a biennial plant, which means it takes two years to complete its life cycle. It grows delicious, edible leaves in its first year and dies back. Then resprouts in the spring of the second year to produce flowers and seeds. Seeds that drop to the ground can sprout the following year as a first-year plant, beginning the cycle anew.

Most gardeners grow parsley as an annual reseeding fresh every year. My parsley garden, however, contains both first and second-year plants, so I have a yearly supply of fresh parsley without having to reseed each year. Second-year plants do have green foliage, but they’re easy to tell apart from first-year plants, as the leaves are long and spindly and definitely not very flavorful.

Growing Conditions

Cilantro — As mentioned above, cilantro is a cool-weather plant and grows best in the spring. You can plant seeds as soon as the soil warms su�ciently. Or sow them in containers, which is what I normally do.

Unfortunately, cilantro will bolt as soon as the weather gets hot, even if only briefly. Here in the Ohio Valley, we usually have a freak 90ºF hot streak over Memorial Day weekend before cooling back down to normal June temps. That small stretch is enough to send plants into flowering mode.

Like most herbs, cilantro prefers loamy, well-draining soil and even watering throughout its short growing cycle.

Parsley — Parsley is much hardier than its cousin, cilantro, and can tolerate a wide variety of conditions. Sow parsley seeds in late spring, when the threat of frost and snow has passed. Seeds will take a while to germinate, so be patient.

 

 

Parsley grows well in loamy, well-draining soil and thrives in full sun or partial shade. I always plant parsley in its own in-ground bed, because it’s quite prolific and, with enough seeding, can grow into a large, bushy bed.

One really cool thing about flat-leaf parsley is that it can survive cold temperatures surprisingly well. In fact, one winter, as an experiment, I draped a row cover over an entire first-year crop, and the plants lasted well into February, full-flavored and everything. Here’s a photo of the experiment in late December that year:

I do believe the plants would’ve lasted even longer if we hadn’t had a significant snowstorm that tore down the row covers and flattened the

bed with wet, heavy snow.

  • What are cilantro and parsley botanically?,

  • How do cilantro and parsley differ in flavor?,

  • What is the life cycle of each herb?,

  • How do their growing conditions compare?,

  • What makes each plant unique in cooking and gardening?

October 16, 2025
October 16, 2025

Thermodynamics and Climate

Imagine you’re driving along a road and you approach a bridge. You notice a sign that reads, “Bridge freezes before road.” Why do bridges become covered with ice before roads do? Research this question and respond in depth, writing a full paragraph. Be sure to include examples. At the end of your response, provide at least two authoritative sources that you used in your research.

Thermodynamics

Thermodynamics is the branch of physics concerned with a system’s energy and work. Scientists became interested in thermodynamics back in the eighteenth and nineteenth centuries, with the birth of the Industrial Revolution. Use online or print resources to answer the following questions about the importance of thermodynamics. Cite at least three authoritative resources to support your responses.

Part A

Thermodynamics and Climate

You’ve learned about the laws of thermodynamics. Using examples, explain why the first and second laws are significant for living organisms.

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Part B

Heat engines were first envisioned and built during the Industrial Revolution. Explain the thermodynamics of a heat engine, commenting on its efficiency.

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Part C

Heat pumps and refrigerators are modern conveniences that came from the study of thermodynamics. In a paragraph, explain how they work.

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Global Warming

Scientists are actively studying what amount of the greenhouse gases present in the atmosphere is a result of human activity. Research greenhouse gases and global warming to answer the questions below. Document at least three authoritative sources.

Part A

What evidence is there that the use of fossil fuels, which produce carbon dioxide, is causing climate change?

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Part B

Describe how computer climate models help scientists understand possible future climate changes. How reliable are these computer models in making predictions about global warming? Discuss any limitations in these models.

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Part C

What can you do? Read up on the issue and discover ways you can reduce the human “carbon footprint” on the planet. Include four examples of what can be done in homes and in the community. Cite your sources.

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Part D

Many people believe that if the human race continues to use energy as we are now, without change, we’ll witness a significant worldwide environmental impact in this century. Research this topic and discuss this possibility. Include concrete examples of specific environmental consequences of global warming.

  • Why do bridges freeze before roads?,

  • Why are the first and second laws of thermodynamics significant for living organisms?,

  • How do heat engines operate and what affects their efficiency?,

  • How do heat pumps and refrigerators work?,

  • What evidence links fossil fuels to climate change?

October 16, 2025
October 16, 2025

Mirrors, Light & Refraction

Discussion – Discuss your experience when standing in front of different types of mirrors in a fun house or even in a clothing store. Why do you look taller or shorter, narrower or wider, or distorted in other ways in these mirrors? Maybe you’ve even seen more than one of yourself in a set of mirrors. Describe your experience. Are these trick mirrors or applications of physics? Explain your answer.

Light Spectrum and Efficiency

You may have already used the Blackbody Spectrum simulation to see how the temperature of a substance affects how light is emitted. Many of the light sources you’re familiar with are incandescent light sources. They glow because they have a nonzero temperature. The hotter the source, the more radiant energy it gives off. Now, let’s explore a few different incandescent energy sources and investigate their lighting efficiency. In this simulation, the curve represents the radiation intensity and energy emitted with respect to the wavelength at a given temperature.

To begin, launch the Blackbody Spectrum https://contentstore.ple.platoweb.com/content/sharedmedia/Phet_Sims_upd/blackbody-spectrum/blackbody-spectrum_en.html

Mirrors, Light & Refraction

Part A

Several different incandescent radiation sources are listed in the table below, along with their respective temperatures. Sunlight is provided as a baseline measurement at the top of the table. You will determine the peak intensity for each source with respect to its visible color spectrum. You also estimate the amount of emitted energy that falls in the visible light spectrum.

To do so

  • drag the slider to reach the temperature listed in the first column of the table. You can also type in the temperature value in the text box above the temperature slider.
  • use the buttons to zoom in or out on either the vertical or horizontal axis to easily observe the curve (and the peak). The peak should be as high as possible, while still being visible on screen. You should extend the scale far enough to the right to see the curve reach very close to zero emission on the right.
  • estimate the percentage of emitted energy that appears to fall within the visible spectrum and enter that value in the table. You can do this by estimating the area under the energy curve in the visible region as compared to the total area under the curve.

Incandescent Light Sources    Temperature(K)   Color at the Peak of the Curve   Energy in

Visible Spectrum

sunlight                                    5800

photoflood                                3400

100-watt incandescent             2870

40-watt incandescent                2500

candle flame                             1900

electric stovetop coil                  800

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Part B

From the readings above, what can you say about the lighting efficiency of the various incandescent radiation sources? Which are the most efficient in emitting visible light?

Support your answer with suitable reasoning.

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Part C Mirrors, Light & Refraction

Compact fluorescent (CFL) bulbs provide about four times as much visible light for a given amount of energy use. For example, a 14-watt CFL bulb provides about the same amount of visible light as a 60-watt incandescent bulb. LED lights are even more efficient at turning electrical energy into visible light. Does that mean they are both a lot hotter? Go online and research how fluorescent and compact fluorescent bulbs work. Describe how their operations and their spectra differ from those of incandescent light bulbs. Be sure to record your research sources.

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Refraction and Refractive Index

Question 1

In this activity, you will use the video measurement and analysis tool, Tracker, to observe how light is refracted when it travels between air and Acrylite, a transparent plastic material. You will also make observations and quantitative readings about the angle of incidence and angle of refraction to find the refractive index of Acrylite.

To begin your activity, open the Tracker experiment Acrylite to Air  contentstore.ple.platoweb.com/content/sharedmedia/Tracker/applications/acrylite-to-air/acrylite-to-air.html .

Click play Play icon. to watch the video. The other video controls allow you to rewind Rewind icon. the video or step forward Step forward icon. or backward Backward icon. one frame at a time.

Observe the video to proceed with the activity, in which you will collect data to calculate the refractive index of acrylite.

Part A

Describe your observations of light traveling from Acrylite into air in the video. Then, compare the relative refractive properties of Acrylite and air. Provide a rationale for any conclusions you may come to.

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Part B

Do you notice any peculiarity in the way the light ray behaves at large angles? Explain this behavior, based on your knowledge of refraction.

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Part C

Now, grab Tracker’s protractor tool (the green angle in the video frame) and measure the angle of incidence and the angle of refraction for the frame numbers specified in the table below. Hints:

  • To advance the video a frame at a time, use the step buttons on the right.
  • Position the vertex of the protractor exactly at the origin of the coordinate axis.
  • Move the arms of the protractor so that one arm is on the vertical axis (above or below, as appropriate) and the other on the light ray.

Frame Number                Angle of Incidence (θi) in Degrees     Angle of Refraction (θr) in Degrees     8

10

12

14

16

18

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Part D

The light ray is traveling from Acrylite into air. The refractive index for air is 1.00. If the angle of incidence and the angle of refraction are known, how could you determine the refractive index of Acrylite?

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Part E

Using the angles of incidence and angles of refraction obtained in question 4, complete the rest of the table below, entering sine values and calculating the refractive index of acrylite for each angle measured. Finally, average these values and enter your calculated average value for the refractive index of acrylite in the space below.

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Part F

Conduct online research to find the refractive index of Acrylite, the material used in the Tracker experiment. (Acrylite is also known as Acrylite glass, or PMMA.) Does the average refractive index you calculated match the accepted refractive index for Acrylite?

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Question 2

Now, open the second Tracker experiment, Air to Acrylite  contentstore.ple.platoweb.com/content/sharedmedia/Tracker/applications/air-to-acrylite/air-to-acrylite.html .

Click play Play icon. to watch the video. The other video controls allow you to rewind Rewind icon. the video or step forward Step forward icon. or backward Backward icon. one frame at a time.

Observe the video to proceed with the activity. In this activity too, you will collect data to calculate the refractive index of acrylite.

Part A

What do you see in this video? Do these observations support your previous findings regarding refractive properties of Acrylite as compared to air? Provide a rationale for your answer.

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Part B

Now, follow the same procedure you did in the earlier Tracker experiment. Find the angle of incidence and the angle of refraction for the frame numbers specified in the table below. Then, calculate the refractive index for Acrylite for this new data. Make a calculation for each measurement in the table. Finally, enter the average of these values in the space below the table.

Frame Number       Angle of Incidence (θi) in Degrees       Angle of Refraction (θr) in Degrees

Sine θi                   Sine θr        Refractive Index

15

20

25

30

35

40

43

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Part C

After researching the actual refractive index of Acrylite on the Web, did you find that it matches your calculations?

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Applications of Convex and Concave Lens

In this activity, you will revisit the two videos about how light is refracted when incident on a lens. First, open the convex lens video. Observe how the light rays parallel to the principal axis behave when they hit the convex lens at different points. You can replay the video any time during this activity.

Then, watch the second concave lens video. Observe how the light rays parallel to the principal axis behave when they hit the lens at different points. You can replay the video any time during this activity.

livephoto.sciencetutorials.net//LPVideos/refl-refr/concave_lens.mp4

Part A

Describe what happens to the incoming parallel rays for the two lenses. Compare and contrast the results.

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Part B

Below is a list of some applications of lenses. Determine which lens could be used in each and explain why it would work. You can conduct online research to help you in this activity, if you wish.

Applications                             Lens Used                                                  Reason

peephole in a door

objective lens (front lens) of binoculars

photodiode – In a garage door or burglar alarm, it can sense the light (or the lack of it) from an LED light source positioned some distance away.

magnifying glass

viewfinder of a simple camera

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Part C

A human eye is a convex lens. In normal eyesight, the image of an object in front of our eyes is formed exactly on the retina and is inverted. In farsighted and nearsighted eyesight, where is the image formed? Which lens can be use as a corrective measure in each case? You may use online or other resources to help you answer this question. Be sure to record your research sources in the References section near the end of this document.

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  • Why do you appear taller shorter narrower or wider in fun house mirrors?,

  • What does the blackbody spectrum reveal about light efficiency in different sources?,

  • How do CFL and LED lights differ from incandescent bulbs?,

  • What are the refractive properties of Acrylite compared to air?,

  • What are the applications of convex and concave lenses in daily life?

October 16, 2025
October 16, 2025

Electromagnetic Fields & DNA

discussion- An enormous amount of electricity is created at power-generating stations and sent across the country through wires that carry high voltages. Appliances, power lines, airport and military radars, substations, transformers, computers, and other equipment that carries or uses electricity all generate electromagnetic fields.

Many questions have been raised about how electromagnetic fields affect our bodies. Do they pose a public health risk? Perform an Internet search to find information about the effects of electromagnetic fields on public health. Then, discuss the pros and cons of using equipment that produces an electromagnetic field.

Here is one authoritative source to get you started: electromagnetic fields and public health.

Electromagnetic Fields & DNA

Double Helix Structure of DNA

This task connects the physics of electrostatics with molecular biology. Molecular biology is the study of the structure and function of the cell at the molecular level. DNA’s double helix structure consists of two strands held together by electrostatic forces. Do online research on electrostatics and molecular biology, and then answer the following questions. Here are two sources to start with:

Part A

What is DNA and what is its role in life? List DNA’s four nucleotide bases.

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Part B

Explain DNA’s structure, specifically noting the role electric fields and forces play in it.

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Electric Field of Dreams

In this activity, you will explore the relationship between the strength and direction of the electric field lines to the type of charge on a particle and its magnitude. You will also explore the interactions between two or more charged particles and observe their movement. To begin your activity, open the simulation: Electric Field of Dreams.  ‪‪Electric field of dreams‬ 1.0.0-dev.10‬

Directions:
At any time you may

  • click the Reset All button to reset all the settings;
  • click the Play/Pause button to pause or resume the motion; or
  • pause the motion and then click the Step button to observe the motion step-by-step.

Part A

To begin, click the Add button to add one object to the system. Observe the electric field around this charged object. You may move the object around the field by dragging it with your cursor. While the arrows indicate the direction of the electric field around the charge, the length of the arrows indicates the field strength. Based on your observations of the field, what is the charge on this object? Give your reasoning.

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Part B

Electromagnetic Fields & DNA

Set the charged object in motion by dragging it and releasing it. What do you observe about the behavior of the field lines in the vicinity of the object?

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Part C

Add another charged object to the electric field by clicking the Add button again. What is the charge of this new object? Give your reasoning. What do you observe about the behavior of both the objects as well as the field lines in the vicinity of both the objects?

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Part D

Click the Remove button to remove one of these objects, and then click the Properties button to set properties for the next object you will add. Just change the sign of the charge to (+), then click Done. Click Add to add this new object to the field. Now what do you observe about the behavior of the two objects and the field lines that surround them?

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Part E

With the two oppositely-charged objects still in the field, apply an external field to the system: In the External Field box, simply drag the dot until it becomes an electric field vector in some direction. Observe, describe, and explain the behavior of the two objects.

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Electric Field Hockey  ‪‪Electric field hockey‬ 1.0.0-dev.10‬

In this activity, you will again explore the relationship between an electric field and charged particles in the field, but this time you’ll have a gaming challenge. To begin, open Electric Field Hockey.

Directions:
On the control bar, make sure that the Puck is Positive and the Field boxes are checked. Also, make sure that the Practice option is selected.

Your aim is to score goals by manipulating the black puck (test charge) into the blue-colored bracket (goal) on the right. Think smart and place positive source charges (red) and negative source charges (blue) in such a way that the black puck moves into the goal.

Note that when you place a red, positive source charge in the hockey field, a red arrow appears on the black puck (test charge) showing the force the positive charge exerts on the puck. Similarly, when you place a blue, negative source charge in the hockey field, a blue arrow appears on the black puck (test charge) showing the force the negative charge exerts on the puck.

Part A

Place a red charge in the hockey field and click Start. In which direction do electric field lines point? In which direction does the black puck move? What conclusion do you draw from this movement?

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Part B

Click Reset and then click Clear. Now, place a blue charge in the hockey field and click Start. In which direction do electric field lines point? In which direction does the black puck move? What conclusion do you draw from this movement?

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Part C

Manipulate the mass of the puck by dragging the Mass bar to the right for increasing the mass and to the left for decreasing it. What changes do you see in the speed of the puck? Which principle works behind this change?

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Part D

In the same situation, what do you observe about the relationship between the speed of the black puck and its distance from the blue charge?

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Part E

You can make the puck travel in complex ways by placing a set of charges around on the field. So, here’s your game challenge: Arrange source charges around to propel the puck from its starting position into the goal. That’s pretty easy for a straight shot; you just put a negative charge behind the goal. But what if there are barriers in the way? That’s a real test of your physics understanding, including Newton’s laws of motion and electrostatic forces. Game’s on!

On the control bar, check the Trace, Field, and Anti-alias boxes. The game has three Difficulty levels. Start with Difficulty level one and arrange source charges to get the puck into the goal. Once you’ve made a score at any level, increase the Difficulty level. Take a screen capture of two of your most difficult goals and paste them here. At least one of these should be at Difficulty level 2 or 3.

(Note: On a Windows computer, you can use the key combination Alt-Print Screen to copy the currently-active window to your clipboard. When you capture an image of this simulation window, paste the image into an image-processing program such as Paint, and save the image as a file. Then use the Insert Image button to insert the file into the response area.)

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  • Do electromagnetic fields pose a public health risk?,

  • What are the pros and cons of using equipment that produces electromagnetic fields?,

  • What is DNA and what is its role in life? List DNA’s four nucleotide bases.,

  • Explain DNA’s structure and the role electric fields and forces play in it.,

  • What did you observe about electric field behavior and charged particle interactions in the simu

October 16, 2025
October 16, 2025

Home Energy Use & Conservation

Discussion-   It’s possible to save a great deal of electrical energy (and money and natural resources) with some simple changes in household electrical use. The trouble is that most of these changes mean either changing behavior or spending money. Do an Internet search and review a few ways to save electrical energy. Discuss at least one change that you think would be reasonable and worthwhile to do in your own home in the next year. Provide your rationale.

Home Energy Use

In this activity, you are going to perform an experiment to track the amount of power you and your family use, then look at some basic patterns in that usage. (NOTE: If you live in an apartment or home in which you do not have access to the electrical meter, consult with your instructor about alternative arrangements, like teaming with a classmate to gather this data.)

This experiment is going to span the course of a full week and require 12 meter readings. It really involves two separate experiments:

  • tracking daily energy use for a week to compare any usage variations from day to day
  • comparing a single high-usage time period of a few hours with a single low-usage time period of a few hours to help you identify the extremes in your household electrical use

Home Energy Use & Conservation

You can easily do both experiments during the same time period. This approach would be the easiest and fastest way to proceed. Read the instructions for both Part A and Part B if you wish to do both experiments at the same time.

To begin, you’ll need to find your electric meter, which could be inside or outside of your home. Many electric meters these days are digital and pretty easy to read, but if you have an older “dial-type” meter, go to this electric meter reading guide to learn about how to read and understand it.

For each of the two experiments below, you will first record three simple pieces of data in a table:

1) day and date, 2) time, and 3) the kWh reading from the meter.

Then record the results of three simple calculations:

  • kWh used: Calculate kWh used since the last reading (subtraction).
  • Hours elapsed: Calculate the number of hours since the last reading (subtraction rounded to a whole number).
  • Average kW used: (kWh used)/(hours elapsed). If this number turns out to be 0.36, for example, it means that your average household power usage for the time period was about 360 watts, the equivalent of running six 60-watt bulbs for that whole time period.

Part A

Daily Electrical Usage: Data Collection

Pick a convenient time of day to take readings from your electric meter. You’ll need readings roughly a day apart, but if they differ by only an hour or two, that should be fine. Pick a consistent time you’ll remember, though, such as after getting home for the day. You need to start by doing an initial meter reading, then follow up with a reading every day for the next 7 days. You’ll do 8 readings in all.

Record your readings in the tables below. In addition to the data fields described above, there is a lot of room for usage notes. Record anything that might have substantially affected the electrical usage since your previous reading. This might include the amount of time people were around and awake at home, use of specific devices such as an air conditioner, clothes dryer, TV, or lighting.

Type your response here:

Initial Reading

day & date

time

kWh reading

Day 1                Data Usage notes (since last reading)

day & date

time

kWh reading

kWh used

hours elapsed  ‘

avg. kW used

Day 2                        Data Usage notes (since last reading)

day & date

time

kWh reading

kWh used

hours elapsed

avg. kW used

Day 3                          Data Usage notes (since last reading)

day & date

time

kWh reading

kWh used     ‘

hours elapsed

avg. kW used

Day 4                                Data Usage notes (since last reading)

day & date

time

kWh reading

kWh used

hours elapsed

avg. kW used

Day 5 Data                 Usage notes (since last reading)

day&date

time

kWh reading

kWh used

hours elapsed

avg. kW used

Day 6           Data                   Usage notes (since last reading)

day & date

time

kWh reading

kWh used

hours elapsed

avg. kW used

Day 7 Data                                                                Usage notes (since last reading)

day & date

time

kWh reading

kWh used

hours elapsed

avg. kW used

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Part B

Usage Extremes: Data Collection

For this experiment, you’ll measure electrical usage during a time period when you expect to have very light electrical usage (for instance, while you’re asleep at night or during the day when no one is at home). Likewise you’ll measure electrical usage during a time period when you expect to have heavier than average electrical usage. This time period might be in the evening, when lights and other appliances are on. Both of these time periods should be at least 4 hours long, to increase the accuracy of your results.

Record your results in the tables below for each situation. For each time period, you’ll need to take an initial and a final reading.

Type your response here:

Low Usage – Initial Reading

day & date

time

kWh reading

Low Usage – Final Reading                             Energy Usage Notes

day & date

time

kWh reading
kWh used

hours elapsed

avg. kW used

High Usage – Initial Reading

day & date

time

kWh reading

High Usage – Final Reading                       Energy Usage Notes

day & date

time

kWh reading

kWh used

hours elapsed

avg. kW used

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Part C

Let’s start the analysis by looking at your “extreme usage” cases. Compare the two cases in detail—low usage period versus high usage period. Discuss differences between the two as well as any surprises. Things you should cover in your discussion: How much difference was there in average power usage (avg. kW) between the low-usage and high-usage time periods? What might have been running during the low-usage period that used energy? Identify likely “stealth” energy users that you could not turn off during the low-usage period. What do you suppose contributed most to the usage during the high-usage period?

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Part D

Having looked at your “extreme usage” cases, analyze your day-to-day usage. Discuss in detail. Specifically, compare higher usage days to lower usage days. Were there significant variations? Do your conclusions regarding the “extreme” cases help to explain any daily variations? What were the surprises or new insights you had in reviewing this day-to-day usage record?

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Part E

It is possible to save a great deal of electrical energy (and money and natural resources) with some simple changes. You’re probably familiar with what some of those changes are and are now more attuned to your own electrical usage. The trouble is, most of these changes either mean changing behavior or spending money. Search the Web for a few ways to save electrical energy. Record them below and categorize them, if possible, as “change behavior” or “spend money.” You might want to consider adding a “neither” category. There are a few things that don’t really require much change or money at all. Include your sources in your answer.

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Part F

Based on what you’ve learned from your household energy investigation, which of these methods seems reasonable to do in your own home this year? (Do you plan to do it?) Provide your rationale.

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What Is “Wasted” Electrical Energy?

Discuss the production, transmission, and usage of electricity in the context of conservation of energy. When electricity is “used” or we say that energy is “wasted,” what is actually happening?

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Electrical Safety Devices

Perform an Internet search to learn about grounding wires, fuses, and circuit breakers. Specifically,

  • describe how each device works; and
  • relate its function to what you’ve learned in this unit about electric current, voltage and resistance.

 

October 16, 2025
October 16, 2025

Electromagnetism & Aurora Discussion

discussion-  Research and discuss the aurora borealis in terms of electric charges, magnetic fields, and forces. Which times of the year are best for seeing the northern lights, and where are the best places to view them? Explain your answers. Also identify links to good images. If you’ve ever seen the aurora borealis, describe your experience and note the time and place that you saw it.

Faraday’s Law

Electric generators use the properties of electromagnetism to transform kinetic energy into electrical energy. Many electric generators work by spinning a permanent magnet near coils of wire. Experiment with this simulation of electricity generation to visualize how this process works. Once the simulation opens, try moving the permanent magnet around to see what happens. Also rapidly switch the polarity of the magnet by repeatedly clicking on the magnet icon at the bottom of the page, and observe the effect.

Part A

Electromagnetism & Aurora Discussion

Try moving the magnet in the different ways described in the table below,. Record your observations in the second column of the table.

Motion                                                            Observations

Move the magnet straight through the coil, leading with the north pole. Once the magnet is completely through, move it back to its original position.

Move the magnet straight through the coil, only this time leading with the south pole. Once the magnet is completely through, move it back to its original position

Put the magnet in the center of the coil, but don’t move it.

Put the magnet on the outside of the coil. Repeatedly move it up and down while outside of the coil.

Keeping the magnet outside of the coil. Repeatedly move it back and forth horizontally.

Place the magnet back inside of the coil. Now repeatedly switch the polarity of the magnet by pressing the button toward the bottom-right of the page over and over again.

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Part B

After producing electricity in many different ways, describe what causes electricity to flow in the coil? In your response, describe the types of forces acting on the electrons and how they result in movement.

 

As you know, loudspeakers are used for communication at sporting events, and in schools or supermarkets. Research loudspeakers on the Web. Describe the components of a speaker and explain how it produces sound. In particular, explain how the force on a current-carrying wire in a magnetic field is used to make a speaker operate.

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Electromagnetism & Aurora Discussion

Throughout this lesson, you learned about the lives and contributions of key scientists in this area of physics. Create a timeline that ties them all together. The timeline does not need to be highly detailed, but it should do the following:

  • Include at least the four major scientists covered in this unit: Oersted, Ampère, Faraday, and Tesla.
  • Include key contributions of each scientist and provide a year, if possible, for those contributions.
  • Note any relationships among these and other scientists, especially if one developed something based on the work of another.
  • Arrange the scientists chronologically by their first key contribution, not by their birth date.
  • Explain how the aurora borealis relates to electric charges magnetic fields and forces,

  • Identify best times and locations to view the aurora,

  • Record observations from Faraday’s Law magnet–coil experiments,

  • Describe what causes electricity to flow in the coil,

  • Explain how a loudspeaker works,

  • Create a timeline for Oersted, Ampère, Faraday, and Tesla.