Bringing Life to Physics Class

Professor Richard Superfine, students in a pyramid

Professor Richard Superfine, left, has his students create a human pyramid to illustrate how atmospheric pressure rises. UNC Department of Physics and Astronomy hide caption

itoggle caption UNC Department of Physics and Astronomy

A University of North Carolina professor is doing his best to shatter the myth that physics classes are difficult and boring.

In one example, Richard Superfine cuts through the dullness by having students pretend to be a train to demonstrate magnetic levitation.

"Students and kids start out with an amazing curiosity about the world around them — an enthusiasm for science," says Superfine, whose class is called How Things Work. "I think what happens, unfortunately, is that they start getting a sense that things are too complicated, that they can't understand what's happening. What we try to do is get kids re-excited about the phenomena they're studying."

Jessica Jones' report concludes an NPR series on the most popular courses on campuses around the country.

Following is one of the "home experiments" Superfine asks his students to perform.

Physics 16: Home Experiment 1

SPLAT! or Does Toast Land Jelly-Side Down?

Equipment needed:

1 slice of bread, toasted (to keep it stiff)

Jelly, any flavor (or peanut butter)

Why does it seem that every time you accidentally knock a freshly jellied piece of bread off of the table, it lands with the jelly side DOWN?

Introduction

In this experiment, we seek to address the issue head on. First, does it in fact preferentially land jelly side down? Perhaps you just remember those cases when you are most hungry. If you do measure a trend (and you probably will), what is the cause? Is it Murphy's Law, which states that nature will conspire to disappoint you? Actually it is Newton who has something to say about this phenomenon. As you proceed through the experiment, feel yourself becoming a scientist, with no insult intended for those who already are. What is a scientist? Someone who wants to know why something happens, speculates on possible reasons, and then performs experiments to find out what nature does. Do the first two without the third, and you are a Greek from 200BC. Do the third, and you are post-Galilean. In general, you will be presented with a variety of questions to guide your observations and design of experiment. It is essential that you improvise. Come up with your own questions and tests. And please forward any lingering questions on your write-up.

Procedure

Make sure that you are not hungry before performing this experiment as watching a perfectly good piece of toast and jelly get ruined on your floor may be too traumatic. And remember, do not put the toast in your eye and do not eat the toast after it has landed on a dirty floor.

1) Toast a piece of bread and spread jelly on one side. Place the toast, jelly side up, near the edge of a table. You may want to place some wax paper or newspaper on the floor. It's your mess!

2) Don’t push it off yet! Make a prediction as to what you think is going to happen! Record it below and provide a justification for why you think the toast will behave the way it will:

3) Gently tap the toast until it falls off of the table, and observe carefully what happens. Does the toast turn over while falling? Once, twice, thrice? Does it bounce? Does it flip upon landing?

4) Perform this experiment 20 times, recording the results in the table supplied on the answer sheet.

5) Was your prediction correct? Explain why or why not.

6) Design two experiments of your own. (Use the questions below to assist in your inquiry if you wish; or come up with one or two of your own curiosity). Predict what will happen. Test your prediction and record observations in a table. Draw conclusions from your results.

Examples of Inquiry

Does it matter how high the table is? Does it matter how fast you push it?

Why does the bread flip? Is it because it is heavier on the jelly side and the heavy side has a greater tendency to land down? How could you test this conjecture?

Last experiment for Home Experiment 1:

Toss a coin in the air 20 times and record the outcomes in the last column of the table.

How does this address the issue of whether your toast results are completely random?

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