Calculate Velocity & Time of Pencil Dropped from Elevator Moving at 5m/s

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To calculate the time and velocity of a pencil dropped from an elevator moving upward at 5 m/s, it's essential to apply Galilean relativity, which states that the laws of physics remain consistent across inertial frames. Initially, the pencil has an upward velocity of 5 m/s, matching the elevator's speed. When dropped, the pencil will experience free fall, and its motion can be analyzed as if it were in a stationary frame. The key is to consider the initial conditions and the effects of gravity on the pencil's descent. Understanding these principles will help in determining the time it takes to reach the elevator floor and its final velocity upon impact.
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A pencil is dropped from inside an elevator moving 5m/s upward. Calulate the time it takes to drop from 1m to elevator floor and its velocity.


I approached as a velosy problem. Is this more of a Force problem ? I could calculate the velocity and time it took while the elevator was at a standstill, but got stuck when its in motion. Can someone please guide me in the right direction? THanks!
 
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maybe show some working so we can see where you went wrong

note the pencil will initially be moving up at 5m/s the same speed as the elevator & have a think about equivalence of inertial reference frames
 
lytien said:
I could calculate the velocity and time it took while the elevator was at a standstill, but got stuck when its in motion. Can someone please guide me in the right direction? THanks!

The concept you should apply is Galilean relativity; the laws of physics are the same in all inertial frames.
 

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