An experimenter measures the length of a rod. In the cases listed, all motions are with respect to the lab and parallel to the length of the rod. In which of the cases the measured length will be minimum?
The new length is given by,
Where, l0 = Length of rod at rest
` c = Speed of light >> v
Consider the rod at rest and observer moves with the speed of v parallel to the measured length then the new length is given by,
Where, l0 = Length of rod at rest
` c = Speed of light >> v
Consider the rod at rest and observer moves with the speed of v opposite to the measured length then the new length is given by,
As v << C
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Thus, l<l0
Thus, the length will be minimum for the rod moving in the opposite direction.
So, correct option is B.
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