PROFESSOR JUSTIN VANDENBROUCKE (PHYSICS 115: ENERGY)
Assignment
Some weeks (about six total) there is an article response assignment. Find an article of your choice (published recently, within the past few months) related to energy and write a response. Your response should critically discuss what was in the article rather than simply summarize it. Please start your response with a link to the original article and a quick summary.
Then move on to analysis of / response to the article. You can explain the physics behind the article, relate it to something we learned in class, point out a mistake, explain why you disagree with something that was written, describe something you didn’t understand, point out that there was important information missing from the article, or do a simple calculation regarding the article.
One of the fundamental goals of this course is for you to become a numerate (in addition to literate) citizen. That is, at the end of this course you should be comfortable reading and judging quantitative information in news articles, and when important quantitative information is incorrect or missing you should be able to recognize this and request the correct information or find it for yourself. Article responses are opportunities to develop this skill. An optional format is to address it as a letter to the editor, in response to the original article. Your response should be short (one or two paragraphs, between 100 and 400 words total).
Article sources
Be careful to use a reputable source for the article you respond to. Good national and international sources include The New York Times, The Wall Street Journal, The Washington Post, The LA Times, The Economist, The Christian Science Monitor, Science, Nature, BBC News, Discover, Scientific American, Popular Science, Science News, and New Scientist. The Wisconsin State Journal, the Capital Times, and the Isthmus are also good sources for energy-related issues on a local scale (Wisconsin and Madison). Avoid blogs unless you know they are high quality.
Responses are due in Canvas Tuesdays at 5:00pm
Post your article in Canvas by navigating to the assignment (there is a separate one for each writing assignment) and clicking the “Submit Assignment” button. This will open a text box where you can enter your assignment. I recommend typing it first in a separate program and then copying it into the text box, in case there is any problem with the internet or Canvas while you are working.
The Writing Center
The UW–Madison Writing Center is a valuable resource for help improving your writing, available in person or online. You can make an appointment or drop in: http://www.writing.wisc.edu.
Grading scale
Article response grading is as follows:
0: not submitted or not submitted on time
8 or lower: submitted on time but poorly done
9: submitted on time and well done
10: submitted on time and outstandingly well done
9 is a good grade. 10 is for responses that are unusually well done.
Your lowest grade from the “writing and other assignments” category (which includes article responses) will be dropped.
Detailed grading criteria (rubric)
What distinguishes a 9 from an 8?
The answer to every question below should be yes, in order to receive a 9 rather than an 8.
• Did you provide a link or reference to the original article?
• Did you choose the article from a reputable source?
• Does the subject of the article relate clearly to energy?
• Did you include a brief (two to three sentence), clear summary of the article?
• Did your analysis of the article include a connection to the physics of energy (rather than focusing exclusively on e.g. economics or public policy)?
• Is the response well written, without spelling or grammar errors?
• Did you provide your own analysis rather than taking analysis from the article?
What distinguishes a 10 from a 9?
The answer to one or more question below should be yes, in order to receive a 10 rather than a 9.
• Is your response particularly interesting and engaging?
• Did your discussion connect the article directly to concepts we have discussed in class?
• Did you include a quantitative discussion/analysis?
• Did you perform a (simple) calculation with numbers either from the article or numbers related to the article that you researched yourself?
• Did you find an error (e.g. confusing energy and power, or using incorrect units) in the article?
• Did you discuss a quantitative aspect of the article that should have been included and was not? For example, if the article was about a new or planned energy source, did the article provide information about how much energy or power the source will provide? This is the first number required on the benefit side of a cost-benefit analysis of an energy source, but is often missing in articles that discuss other aspects in detail.
A SAMPLE STUDENT RESPONSE IN PHYSICS
Rebekah Ottoway
March 6th, 2018
Article Response 3
Physics 115: Energy (Prof. Vandenbroucke)
https://www.sciencedaily.com/releases/2018/02/180215180313.htm
In this article from Science Daily, a research team at Virginia Tech are finding new ways to melt the stubborn piles of snow left in parking lots, ditches, and driveways after a snowstorm. They have invented a thermal absorptive blanket equipped with artificial sunlight to speed up the melting process. Their “Melt Mat” received a journal publication and a patent for this technology. The team took a year to get a perfect design that is not only affordable but is also durable. The Melt Mat is environmentally safe and can be used repeatedly compared to other methods of snow removal which are one time use. With the patent on the Melt Mat, the team could possibly have a very profitable future off of their invention.
The fundamental problem the team is addressing is the reflection of light off the snow, rather than absorption to aid melting. Because the snow doesn’t absorb sunlight well, it doesn’t increase its kinetic energy, and therefore stays close to the same temperature even when the temperature increases outside. Structurally, the Melt Mat is made of an aluminum sheet with a coating of black paint. The black color’s role in heat absorption is to increase the amount of sunlight absorbed to help make up for the lack of sunlight absorbed of the white snow. The energy absorbed by the black mat will then be transferred to the snow through conduction, resulting in a melting time of the snow that is decreased to one-third the time without any use of energy. To measure the amount of energy needed to melt 20 kilograms of snow, you would calculate Q using this equation:
Q = m * heat of fusion (of water). So, Q = 20kg * 4.184 J / kg = 83.68 J of energy used to melt 20 kg of snow at a constant temperature. To calculate the rate of heat conduction from the Melt Mat to the snow can be measured by the equation: H = A* T/r. Since we already know how to solve Q from the previous equation, we can find H but we need to know the resistance of the aluminum in order to solve it. The Melt Mat should have a low resistance in order to transfer heat to the snow efficiently.