What is the (a) force of gravity and (b) weight of a block of mass 10.5 kg? Take g = 10 m s^-2

A ball is released from a height and it reaches the ground in 3 s. If g = 9.8 m s^-2, find —

(a) the height from which the ball was released,

(b) the velocity with which the ball will strike the ground.

A ball is thrown vertically upwards. It goes to a height 20 m and then returns to the ground. Taking acceleration due to gravity g to be 10 m s^-2

find —

(a) the initial velocity of the ball

(b) the final velocity of the ball on reaching the ground and

(c) the total time of journey of the ball.

A body is dropped from the top of a tower. It acquires a velocity 20 m s^-1 on reaching the ground. Calculate the height of the tower. (Take g = 10 m s^-2)