# Unit 7 Extra Credit

Either print this page and complete or (better yet) neatly show your answers on a separate page of paper. All answers must be expressed as complete sentences and/or all work shown to receive credit.

1. If you were traveling with respect to the stars at a speed close to the speed of light (300,000 km/s) you could detect it because

B. your heart would slow down.

C. you would shrink.

D. all of the above

E. you could never tell your speed by changes in you

Explain why you picked the answer you did.

2. Which of the following facts, if definitely established, would violate the "Theory of Relativity" as we know it today?

A. Things can go faster than the speed of light.

B. Nothing can go faster than the speed of light.

C. If a thing goes faster than light, it quickly slows to a speed less than that of light.

Explain why you picked the answer you did.

3. Suppose a rocket ship departs from the earth at noon and travels at the same high speed for one hour rocket time. During this hour it emits a flash every 6 minutes, ten in all. An earth observer sees these flashes at 12- minute intervals. When the 10th flash is emitted, clocks aboard the rocket ship read 1:00. When the 10th flash is received on earth, what would the clocks on earth read?

4. Suppose the above rocket ship is able to abruptly turn around when the 10th flash is emitted and head back to earth at the same high speed. It sends flashes every 6 minutes or 10 in one hour, but the flashes on earth are seen every 3 minutes. The clock on the rocket reads 2:00 when the ship gets back to earth (1 hour out and 1 hour in), what would the clocks on earth read?

5. Strictly speaking, from the point of view of a person on the ground floor of a tall skyscraper. a person at the top ages

A. slower B. faster C. the same

Explain why you picked the answer you did.

Resources for physics students are available through links on the GBS Physics Home Page. Such resources include the Multimedia Physics Studios (a collection of animations and movies which illustrate key physics concepts) and The Physics Classroom (an online tutorial written in an easy-to-understand language).