Prove that if a body is thrown vertically upward, the time of ascent is equal to the time of descent.

A girl running a race accelerates at $2.5\, m s ^{-2}$ for the first $4\, s$ of the race. How far does she travel in this time ?

The position$-$time graph for the motion of a car is given below

$(i)$ How far the car tavelled in the time interval $2$ to $6 s ?$

$(ii)$ During which interval of time its speed was more?

$(iii)$ Calculate the average speed of the car.

An electron moving with a velocity of $5 \times 10^{4}\, ms ^{-1}$ enters into a uniform electric field and acquires a uniform acceleration of $10^{4}\, ms ^{-2}$ in the direction of its initial motion.

$(i)$ Calculate the time in which the electron would acquire a velocity double of its initial velocity.

$(ii)$ How much distance the electron would cover in this time ?

Area under velocity$-$time graph is equal to the