Q18 of 37 Page 22

A ball is thrown from a roof top at an angle of 45° above the horizontal. It hits the ground a few seconds later. At what point during its motion, does the ball have

(a) Greatest speed.


(b) Smallest speed.


(c) Greatest acceleration?


Greatest speed will be experienced when ball will just reaching the bottom ground, as at time all the potential energy will be completely converted to kinetic energy hence maximum speed will be experienced


Smallest speed will be at highest point, as only single component will be present at time (horizontal), therefore at that time vector sum of velocity will be lowest.


Acceleration is only due to gravity; hence it will remain constant throughout (if we are not considering air drag as this will convert it into non-uniform motion)


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