InterviewSolution
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InterviewSolution
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y drops a stone from the top of a building 100 m high. Another boy throws an iron ball 2seconds after the stone was dropped. Calculate the velocity with which the iron ball was thrownso that both the stone and the iron ball strike the ground at the same time. |
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Answer» For the stone that is dropped, Initial velocity, u = 0 Distance covered, h = -100 m Acceleration due to gravity, g = -10 ms-2 h= ut+1/2gt^2-100= 0-1/2*10*t^2t= 4.5 secondSo, the stone reach the ground in 4.5 s after it is dropped. Now, at t = 0, the iron ball is thrown. At, t = 2 s, the stone is dropped. So, the stone reach the ground at t = 2 + 4.5 = 6.5 s Which means the iron ball was in air for 6.5 s. For the iron ball, Initial velocity is say, v Final velocity will be –v Acceleration due to gravity, g = -10 ms-2 Time of flight, t = 6.5 s -v= v+gt-v=v-10*6.5 2v= 65v= 32.5m/s So, the iron ball has to be thrown at a speed 32.5 m/s to make both the projectiles reach the ground at the same time. HIT THE LIKE BUTTON IF YOU ARE SATISFIED thank you |
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