A 10 kg ball is thrown upwards with a speed of 5 m/s. (a) Find its potential energy when it reaches the highest point. (b) Calculate the maximum height it reaches.
Initial KE = (1/2) (10) (5)2 = 125 Joule
(a) PE at the highest point = KE at the lowest point at initial moment = 125 J
(b) Max height = H = (u)2/(2g) = 25/(2×9.8) = 1.27 m