Special relativity test questions

Which of the following has not been observed to change due to motion?

An astronaut takes a long space journey at close to light speed. The astronaut's twin sister remained on Earth. On a return to Earth, what is the astronaut's age compared to her earthbound twin?

As it approaches the speed of light, what will happen to the length of a spacecraft as observed by a passenger inside?

A spacecraft of length 780 metres is travelling at a constant speed of \(0.95 c\). The spacecraft travels at this speed for 10 years, as measured by a clock on the Earth.

Calculate the time elapsed, in years, as measured by a clock in the spacecraft.

A spacecraft of length 780 metres is travelling at a constant speed of \(0.95c\). The spacecraft travels at this speed for 10 years, as measured by a clock on the Earth.

If the spacecraft passes Earth at this speed what length would an observer on Earth measure for the spacecraft?

Imagine a train travelling at \(100ms^{-1}\) with a passenger who throws a ball ahead of the train at \(5ms^{-1}\).

What is the resultant velocity of the ball?

Imagine a train is travelling at \(2.9 \times 10^{8}ms^{-1}\).

A passenger shines a torch from the front of the train.

What speed does the passenger see the light from the torch move at?

Imagine a train is travelling at \(2.9 \times 10^{8}ms^{-1}\).

A passenger shines a torch from the front of the train.

A stationary observer on the train platform measures the speed of light from the torch.

How fast does the light appear to move according to the stationary observer?