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In difining the standerd of length, we h...

In difining the standerd of length, we have to specify the temperature at which the measurement should be made. Are we justified in calling length a fundamental quantity, if another physical quantity (temperature) has to be specified in choosing a standeard?

Text Solution

Verified by Experts

The length of an object changes with
temperature but the unit for measuring length
(i.e., metre) has now been defined in terms of
wavelength of light. This is not affected by
temperature. Hence, the choice of length as a
fundamental units is justified.
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