$A$ train is travelling at a speed of $90\, km \,h^{-1}$. Brakes are applied so as to produce a uniform acceleration of $-0.5\, m s^{-2}$. Find how far (in $m$) the train will go before it is brought to rest.

$A$ ball is gently dropped from a height of $20 \, m$. If its velocity increases uniformly at the rate of $10 \, m s^{-2}$,with what velocity will it strike the ground? After what time will it strike the ground?

During an experiment, a signal from a spaceship reached the ground station in five minutes. What was the distance of the spaceship from the ground station? The signal travels at the speed of light, that is, $3 \times 10^{8} \, m \, s^{-1}$.

$A$ stone is thrown in a vertically upward direction with a velocity of $5 \, m s^{-1}$. If the acceleration of the stone during its motion is $10 \, m s^{-2}$ in the downward direction,what will be the height attained by the stone and how much time will it take to reach there?

Distinguish between speed and velocity.

Which of the following is true for displacement?