A lift is moving upward at 10 m/s and accelerating upward at 2 m/s². A bolt detaches from the ceiling 3 m above the floor. Take g=10 m/s². Time taken by the bolt to hit the floor is:
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A lift is moving upward at 10 m/s and accelerating upward at 2 m/s². A bolt detaches from the ceiling 3 m above the floor. Take g=10 m/s². Time taken by the bolt to hit the floor is:

G1 Physics · Accepted Answer

At detachment, bolt and lift have the same velocity, so initial relative velocity is zero. Relative acceleration downward is g+a=12 m/s². Thus 3=(1/2)(12)t² ⇒ t²=1/2 ⇒ t=1/√2 s.