Lights Out

Your brain was not meant to be knocked about. Keeping it safe, supported and stable seems like common sense. Yet, we live in a society in which contact sports sometimes result in concussions. By modeling these events in mice, scientists are learning more about the process and consequences of head-banging. Results show that mice subjected to brain-jarring demonstrate impaired mental functions when compared to control animals.

By Michael DiSpezio|Wednesday, November 24, 2004


Softening the Impact

There are a variety of devices and strategies that reduce the impact of collision. Most depend upon the gradually decelerating the moving object(s). In this activity, you’ll create a simple device to soften the impact of a hurled egg. The egg’s rapid deceleration will protect it from cracking on impact. But don’t take our word for it. Try it yourself and see.

Safety goggles
Old bed sheet
Curtain rod
Curtain rings
Sealable plastic bags
Needle and thread

1. Make sure wall hangers support the curtain rod across a doorway. Students must not hold the curtain rod in place.

2. The egg must be placed in a sealed plastic bag before it is thrown.

3. Before throwing the egg, everyone in the room must put on a pair of safety goggles. 

1. Obtain an old sheet. Sew a pouch along its bottom margin. The pouch should be about 5 inches (7.5 cm) wide.

2. Use a waterproof marker to draw a bull’s-eye in the center of the sheet.

3. Punch holes along the top edge of the sheet into which curtain rings can be inserted.

4. Insert the rings into the holes. Then pass the rings onto a curtain rod.

5. Support the curtain rod on hangers that extend across an open doorway.

6. Place an egg in a plastic bag. Seal the bag.

7. Make sure that everyone in the classroom is wearing protective safety goggles. Also ensure that no one is behind the doorway.

8. Toss an egg at the target. What happens when the egg strikes the sheet?

9. Try again but increase the speed of the throw. What happens now?

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1. What happened to the sheet when the egg struck it? (The sheet moved backward.)

2. What happened to the kinetic energy of the moving egg as it struck the sheet? (Most was transformed into the movement of the sheet.)

3. Why did the sheet move only a small distance? (The sheet had a large mass so when the egg struck it, the energy dissipated over the mass of the entire sheet.)



Color My World
Obtain several sheets of colored transparent plastic. Observe your surroundings while looking through these colored filters. Suppose you looked at an object the same color as the filter? What color would the object appear? Make a guess. Then try it and find out. Can you explain your observations based on the behavior of transmitted and reflected colors?

Safety Posters
Although it is fun, bike riding can be hazardous to your health – especially if you don’t wear a protective helmet. Create a poster that communicates this safety message to your classmates. Are there other ways to reach this audience? How might you best convince everyone to wear helmets while biking?

Changing Society
Do you think you can change society’s view of contact sports? If so, how? Suppose you wanted to inform the general public about the dangers of concussions. What challenges might you face? What strategy or approach would you use?


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