Afast train, the relativity express, is moving along a straight track at a large fraction of the speed of light. two outside observers measure the length of the train. observer a is stationary with respect to the track and observer b is moving parallel to the track in the direction opposite the train at a large but constant speed. you are riding in this train and you, too, measure its length. the length you measure will be than the measurements of either a or b.

The length you measured as an observer in the moving train will be smaller than the measurements of either A or B

Explanation:

This is a phenomenon regarded as length contraction and it is one of the consequences of Lorentz transformation. This is usually felt when we are operating in a speed closer or equal to the speed of light.

The length of any object in a moving frame will smaller in the direction of motion, or contracted. The amount of contraction can be determined from the Lorentz transformation. The length is maximum in the frame in which the object is at rest.

As it is given in the attachment, the observer A will be in the fixed frame and will experience no contraction in length while you will be in the moving frame and experience length contraction.

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