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Chapter 36: Q. 21 (page 1059)

At what speed, as a fraction of c, will a moving rod have a length60% that of an identical rod at rest?

Short Answer

Expert verified

The speed is0.8c.

Step by step solution

01

Given Information

We need to find the peed, as a fraction of c, will a moving rod have a length 60%that of an identical rod at rest.

02

Simplify

The moving rod is the frameS'and the ground frame is S.The length of rod is S'is the proper length lbecause the rod is at rest is S'.

L=1-β2l

The length is calculated to 60%when

L=0.6l1-β2=1-v2c2=0.6v=0.8c

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Most popular questions from this chapter

In an attempt to reduce the extraordinarily long travel times for voyaging to distant stars, some people have suggested traveling at close to the speed of light. Suppose you wish to visit the red giant star Betelgeuse, which is430lyaway, and that you want your 20,000kgrocket to move so fast that you age only 20yearsduring the round trip.

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