A ball is thrown vertically upwards. It returns 6 s later. Calculate (i) the greatest height reached by the ball, and (ii) the initial velocity of the ball. (Take g = 10 m s^-2 )

A pebble is thrown vertically upwards with a speed of 20 m s^-2. How high will it be after 2 s ? (Take g = 10 m s^-2)

A body falls from the top of a building and reaches the ground 2.5 s later. How high is the building ? (Take g = 9.8 m s^-2)

A ball is thrown vertically upwards with an initial velocity of 49 m s^-1. Calculate: (i) the maximum height attained, (ii) the time taken by it before it reaches the ground again. (Take g = 9.8 m s^-2)