- #1
goonking
- 434
- 3
Homework Statement
A Bouncy ball is dropped from a window, 28.7 meters above the ground. It bounces inelastically off the ground and bounces up again, but not as high as it stated out. If it looses 9 percent of its kinetic energy every time it hits the ground, how many times can it bounce, and still have a maximum height greater than half the original window height.
Homework Equations
1/2 mv^2 = mgh
The Attempt at a Solution
Since I know it loses 9% of its kinetic energy, the potential will be lowered by 9% each time the ball bounces also.
So I did 28.7 - (0.09 x 28.7) = 26.1
then 26.1 - (0.09 x 2.61) = 23.76
then 23.76 - (0.09 x 23.76) = 21.627
and so on, I keep repeating this until I get an answer below 28.7 / 2 = 14.35 meters.
And after all that, I get the answer to be 7 bounces.Is there a faster way to do this problem?