Calculate the time of flight of the bolt from ceiling to floor

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SUMMARY

The discussion focuses on calculating the time of flight of a bolt dropped from the ceiling of a lift that is accelerating upwards at 1.5 m/s². The initial upward speed of the lift is 2.0 m/s, and the bolt is 3.0 m from the floor when released. The correct approach involves using the equations of motion, specifically x(f) = x(i) + V(xi)t + (1/2)a(x)t², to account for both the bolt's downward motion and the lift's upward motion. The final calculated time of flight for the bolt is 0.73 seconds.

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Motion question - please help

Homework Statement


A lift ascends with an upward acceleration of 1.5ms^(-2). At the instant its upward speed is 2.0ms^(-1), a loose bolt drops from the ceiling of the lift 3.0m from the floor. Calculate:
(a) the time of flight of the bolt from ceiling to floor

Homework Equations


x(f) = x(i) + V(xi)t + (1/2)a(x)t^(2)

final position = initial position + (initial velocity x time) + (0.5 x acceleration x time^(2))

The Attempt at a Solution



I attempted to solve this question by forming 2 equations and solving it, since when the bolt leaves the roof of the lift and by the time it reaches the floor of the lift, the lift would've moved up:

BALL: x(f) = 0.5 x (-9.8) x (t^(2))

LIFT: x(f) = 3 + 2t + (0.5 x 1.5x t^(2))

answer: 0.73sec

from the two above equations I could't get the right answer, so can someone please tell me if I've formed the right equations? Thanks in advance...
 
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Look at the problem statement carefully.

Initially, until the bolt becomes free, it is traveling with the lift, and it has the same upward initial velocity as the lift at the moment it becomes free.

So rewrite BALL: x(f) = 0.5 x (-9.8) x (t^(2)) with the correct initial conditions

Also realize that the initial position of the bolt is 3 m above the inital position of the floor.
 


Astronuc said:
Look at the problem statement carefully.

Initially, until the bolt becomes free, it is traveling with the lift, and it has the same upward initial velocity as the lift at the moment it becomes free.

So rewrite BALL: x(f) = 0.5 x (-9.8) x (t^(2)) with the correct initial conditions

Also realize that the initial position of the bolt is 3 m above the inital position of the floor.

Thanks for your reply, I never thought of that... Thanks again. :)
 

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