How Does Balloon Motion Impact Stone's Fall Time?

AI Thread Summary
The discussion focuses on how the motion of a balloon affects the fall time of a stone dropped from it. When the balloon ascends at 5 m/s, the stone has an initial upward velocity of 5 m/s, while if the balloon descends at the same speed, the stone's initial velocity is downward. In the case of a stationary balloon, the stone simply falls under the influence of gravity. The key question revolves around determining the initial velocity of the stone based on the balloon's motion at the moment of release. Understanding this initial velocity is crucial for calculating the time it takes for the stone to reach the ground.
kerol9904
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Homework Statement


A stone is dropped from a balloon at an altitude of 300 metres. How much time is required for the stone to reach Earth if:
(1) Balloon is ascending with a velocity of 5 m/s,
(2) Balloon is descending with a velocity of 5 m/s
(3) Balloon is stationary
Disregard air resistance.

Homework Equations


x=x_0+v_0t-1/2gt^2
v=v_0-gt

The Attempt at a Solution


I have no problem with question 3 but I fail to understand how the ascend or descend of balloon affect the stone. I assumed that it affected the initial velocity of the stone but I can't seem to find the formula for time.
 
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What's the initial velocity of the stone when it's dropped from a moving platform? ("Dropped" means it's simply released).
 
The question is about how to understand the initial velocity. When the balloon is moving upward (ascending) the object will have an upward initial velocity upon releasing, of course with the same magnitude as the balloon ascending. and vice versa in the case of downing.
 
Is it the same as the velocity of the platform itself?
 
kerol9904 said:
Is it the same as the velocity of the platform itself?

Yes, as I said above.
 
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