A ball is thrown vertically upward with a velocity of these 30 metre per second if the acceleration due to gravity is 10 metre per second what will be the distance travelled by it in the last second of motion before again come to his hand

v=0 when it reaches the top therefore t  = (0-30)/-10 = 3 sec. It will take 3 sec to come back to the hand. And max height reached h = ½ x 10 x 3x 3 = 45 m. Now in 2 sec after it reaches the summit, it travels ½ x 10 x 2 x 2 which is 20 m therefore in the last or the 3^rd second it will travel 45m – 20m which is 25 m