Special relativity tells us that someone sprinting will shrink, or undergo length contraction, along the direction of motion relative to someone at rest. The world's fastest sprinters, like Usain Bolt, can reach speeds near 13.0 m/s. How fast would they have to run so that their length contraction was (a) equal to the width of a human hair (50.0 µm) and (b) equal to the width of an atom (1.00 × 10-10 m)? Assume the width of the sprinter's body at rest is 25.0 cm. (a) Number i 2.998E8 (b) Number i 2.998E8 Units Units m/s m/s

Special relativity tells us that someone sprinting will shrink, or undergo length contraction, along the direction of motion relative to someone at rest. The world's fastest sprinters, like Usain Bolt, can reach speeds near 13.0 m/s. How fast would they have to run so that their length contraction was (a) equal to the width of a human hair (50.0 µm) and (b) equal to the width of an atom (1.00 × 10-10 m)? Assume the width of the sprinter's body at rest is 25.0 cm. (a) Number i 2.998E8 (b) Number i 2.998E8 Units Units m/s m/s

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter39: Relativity

Section39.2: Special Case: Galilean Relativity

Problem 39.2CE: Suppose the primed and laboratory observers want to measure the length of a rod that rests on the...

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