Calculating Time and Energy Loss for a Bouncing Rubber Ball

AI Thread Summary
To solve the problem of a rubber ball dropped from a height of 2m, the first part can be addressed using the equation of motion to calculate the time until it hits the ground. For the second part, the ball loses 10% of its kinetic energy with each bounce, which leads to a geometric progression in the time taken for subsequent bounces. The initial velocity after the first bounce can be determined and used to find the time intervals for each bounce. By summing these intervals, the total time until the ball comes to rest can be calculated. Understanding the geometric progression is key to solving the second part of the problem effectively.
aurao2003
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Homework Statement


Hi
I am struggling with this question. It goes like this:

A rubber ball is dropped on to flat ground from a height of 2m.
(a) Calculate how long it takes for the ball to first hit the ground.

(b)The ball loses 10% of its kinetic energy at each bounce. Calculate the time taken for the ball to come to rest.

I am able to solve the first part using equation of motion.
S=UT +0.5aT^2

I am not sure of the second part.




Homework Equations





The Attempt at a Solution

 
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hi aurao2003! :wink:
aurao2003 said:
(b)The ball loses 10% of its kinetic energy at each bounce. Calculate the time taken for the ball to come to rest.

find the initial velocity, immediately after the first bounce, and use that to find the time between the first and second bounces

then do the same for all the bounces, and add them …

what do you get? :smile:
 
tiny-tim said:
hi aurao2003! :wink:


find the initial velocity, immediately after the first bounce, and use that to find the time between the first and second bounces

then do the same for all the bounces, and add them …

what do you get? :smile:

It seems to be forming a geometric progression. Is that right?
 
s'right! :biggrin:
 
Cheers!
 
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