Crazy elevator
Level
2
An elevator car whose floor to ceiling distance is equal to 2.7m starts ascending with constant acceleration 1.2 meter per second square , 2 second after the start a bolt begin falling from the ceiling of the car. Find the bolt's free fall time(in seconds).
The answer is 0.7.
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1 solution
Since the elevator is accelerating upward at a constant rate, the apparent gravity inside the elevator will be a = 1 . 2 + g ≈ 1 . 2 + 9 . 8 = 1 1 s 2 m
Under this apparent gravity, an object will fall h = 2 . 7 m in t = a 2 h ≈ 0 . 7 0 0 6 4 9 0 5 s