Q23 of 89 Page 51

A ball is projected vertically upward with a speed of 50 m/s. Find (a) the maximum height, (b) the time to reach the maximum height, (c) the speed at half the maximum height. Take g = 10 m/s2.

Given, initial velocity, u=50 m/s


g=a=-10 m/s2


a. We know at highest point velocity, v=0


Also, distance s is





b. Time taken, t is





a. Here s=125/2=62.5 m


We know,



i.e.




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