Question

A meterstick moves past you at high speed. In your reference frame, you measure that the length of the meterstick is only 1 foot. How fast is the meterstick moving?
a) 0.9071c

b) 0.9524c

c) 0.8660c

d) 0.7670c

Answer 1

here,

the original length , L0 = 1 m

the measured length , L = 1 foot = 0.304 m

let the speed of meterstick be v

we know

L = L0 * sqrt(1 - (v/c)^2 )

0.304 = 1 * sqrt(1 - (v/c)^2 )

solving for v

v = 0.9524c

the speed of meterstick is b) 0.9524c