A person travelling in a fast spaceship measures the distance between the earth and the moon. Is it the same, smaller or larger than the value quoted in this book?

There are two ways to measure the distance between the Earth and the Moon which are using meter scale and using light pulse.


In the first method the distance is measured using meter scale, the length gets contracted in moving frame. Thus, the length measured is smaller.


In second method, the time difference between emission of light pulse and reception is noted. So, the distance measured in this case is larger.


Thus, the distance measured is either smaller or larger than the actual distance.


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