An experimenter measures the length of a rod. Initially the experimenter and the rod are at rest with respect to the lab.

Monjur Alahi

An experimenter measures the length of a rod. Initially the experimenter and the rod are at rest with respect to the lab. Consider the following statements. 

(A) If the rod starts moving parallel to its length but the observer stays at rest, the measured length will be reduced. 

(B) If the rod stays at rest but the observer starts moving parallel to the measured length of the rod, the length will be reduced. 

(a) A is true but B is false

(b) B is true but A is false 

(c) Both A and B are true

(d) Both A and B are false.


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Salim Ahmed Kawsar

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(c) Both A and B are true

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