SOLUTION: Bouncing Ball A ball is dropped from a height of 9 ft. The elasticity of the ball is such that it always bounces up one- third the distance it has fallen. (a) Find the total dis

Algebra.Com
Question 1190153: Bouncing Ball A ball is dropped from a height of 9 ft. The
elasticity of the ball is such that it always bounces up one-
third the distance it has fallen.
(a) Find the total distance the ball has traveled at the instant
it hits the ground the fifth time.
(b) Find a formula for the total distance the ball has traveled
at the instant it hits the ground the nth time.

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
hits ground once: 9 feet
bounces up 3 feet (12)
bounces down 3 feet (15)
bounces up 1 foot and back down 1 foot (17 feet) - has hit floor 3 times
bounces up 1/3 foot and back down 1/3 foot (17 2/3 ft)- 4 times
bounces up 1/9 foot and back down 1/9 foot (17 8/9) feet, the answer.
-
9+2*{3*(1/3)^0+3*(1/3)^1+3*(1/3)^2+3*(1/3)^3...}
the infinite sum is 9+2*3/(1-1/3)=18 feet.
The n th time is 9+ 2*9(1/3)*{{1-(1/3)^(n-1)/(1-(1/3)}, and when n=5, the answer is 17.89 or 17 (8/9).

RELATED QUESTIONS

A ball is dropped from a height of 80 ft. The elasticity of this ball is such that it... (answered by Alan3354)
A ball dropped from a certain height rises after bouncing to 45% of its original height.... (answered by Theo)
A ball dropped from a certain height rises after bouncing to 25 % of its original... (answered by richard1234)
7. A ball dropped from a certain height rises after bouncing to 25 % of its original... (answered by mananth)
A ball that bounces up half the distance from which it is dropped is released one metre... (answered by htmentor)
A ball rebounds one-half the height from which it is dropped. The ball is dropped from a (answered by josmiceli)
A ball rebounds one-half the height from which it is dropped. The ball is dropped from a... (answered by ikleyn)
A BALL BOUNCES TO 65% OF ITS PREVIOUS HEIGHT AFTER EACH BOUNCES. IF THE BALL IS DROPPED... (answered by amoresroy)
a ball is dropped from a height of 2 meters and bounces up to 3/4 of its previous height... (answered by Shin123,ikleyn)