Bouncing ball elastic collision

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The discussion centers on calculating the time taken for a bouncing ball to come to rest after multiple elastic collisions with the floor. It highlights that the speed after each bounce is reduced by a factor of e, where e is less than 1. The proposed method involves using impulse to determine the change in momentum for each bounce and summing these changes as an infinite series. Additionally, it suggests treating the force as constant to simplify calculations using work-energy principles. The approach aims to derive the total time by substituting the calculated force and distance into the equations.
anand
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A ball drops to the floor and bounces,eventually coming to rest.Collisions between the ball and floor are elastic;the speed after each collision is e times the speed before collision where e<1.If speed just before 1st bounce is v,find the time taken to come to rest.
 
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Do you have any thoughts on the question yourself? Could I also ask that in future you would post homework questions using the template provided.
 
Here is how I thought of doing it.
Use impulse=change in momentum
for successive bounces and add them all up(infinite series).Assume the force F to be a constant,so that it can be taken out of the integral sign.To find force F,use
work=change in kinetic energy.
The distance traveled by the ball can be found as sum of an infinite series.
Substituting the value of F,time can be found.
Is this approach correct?
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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