Question

Which one of the following statements is NOT a consequence of the postulates of special relativity?

A) The mass of an object moving with respect to an observer is larger than the mass measured by a different observer who is at rest with respect to the object.
B) A clock moving with respect to an observer ticks more slowly than when measured by an observer who is moving along with the clock.
C) The length of an object moving with respect to an observer is shorter than it is when measured by a different observer moving along with the object.
D) The wavelength emitted from a source moving with respect to an observer is different from the wavelength measured by an observer who is moving along with the source.

Answer 1

The incorrect statement not aligned with the postulates of special relativity is that an object's length appears to increase when viewed by a stationary observer as it approaches the speed of light. In reality, special relativity predicts length contraction, not expansion.

Step-by-step explanation:

The statement that is NOT a consequence of the postulates of special relativity is:

D) When the speed of an object approaches the speed of light, its length appears to increase when viewed by a stationary observer.

This is incorrect because, according to the postulates of special relativity, an object in motion relative to an observer experiences length contraction, not expansion. The proper length of an object is the length measured by an observer moving with the object, and this length is always greater than the length measured by an observer in relative motion to the object at high speeds. Additionally, concerning the wavelength of light, there is a redshift or blueshift for light from a source that is moving away from or towards an observer, respectively, known as the Doppler effect for light.