In defining the standard of length we have to specify the temperature at which 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 standard?

In defining the standard of length we have to specify the temperature

1.	In defining the standard of length we have to specify the temperature at which 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 standard?
Answer» Solution :Yes, LENGTH is a fundamental quantity, one METER is the DISTANCE that contains 1650763.73 wavelengths of orange-red light of Kr-86. Hence, the standard meter is independent of temperature. But the length of object varies with temperature and is given by the RELATION `L_(t=)L_0(1+alphat)` Therefore, we usually specify the temperature at which measurement is MAX.

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In defining the standard of length we have to specify the temperature at which 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 standard?

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