Quiz – Length Contraction

A train with a resting length of 275 m is travelling very fast relative to a stationary observer. The train appears 182 m long to the stationary observer. How fast is the train moving relative to the observer (in c)? Answer using numbers only (i.e. '0.75' for an answer of 0.75c).

A train with a resting length of 275 m is travelling at 40.0% of the speed of light relative to a stationary observer. How long will the train appear to the stationary observer? Answer in metres, using numbers only (i.e. '1.9' for an answer of 1.9 m).

A train with a resting length of 225 m is travelling at 0.140c relative to a stationary observer. How long will the train appear to the stationary observer? Answer in metres, using numbers only (i.e. '1.9' for an answer of 1.9 m).

A train with a resting length of 275 m is travelling very fast relative to a stationary observer. The train appears 272 m long to the stationary observer. How fast is the train moving relative to the observer, as a percentage of the speed of light? Answer using numbers only (i.e. '72.5' for an answer of 72.5% of the speed of light).

A train with a resting length of 205 m is travelling very fast relative to a stationary observer. The train appears 128 m long to the stationary observer. How fast is the train moving relative to the observer (in m/s)? Answer using numbers only (i.e. '282000000' for an answer of 2.82 x 10^8 m/s).