Displacement covered by first ball,(180−100)=0+21×10×t2 ⇒t=4s
Now, the second body gets only, t2=4−2=2s.
Displacement covered by second will be same,
80=u×2+21×10×(2)2
⇒u=280−20=30ms−1
Two balls A and B are placed at the top of 180m tall tower. Ball A is released from the top at t=0s. Ball B is thrown vertically down with an initial velocity u at t=2s. After a certain time, both balls meet 100m above the ground. Find the value of u in ms−1. [use g=10ms−2]
Held on 29 Jun 2022 · Verified 6 Jul 2026.
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