a Find the rebound ratio for the ball using the given information.
B
b Use your result from part A and the rebound ratio.
C
c Use your result from part B and the rebound ratio
A
a 5.55 ft
B
b 3.08 ft
C
c 1.71 ft
Practice makes perfect
a According to the information in Exercise 15-18, a tennis ball must rebound approximately 111 cm when dropped from 200 cm. With this in mind, we need to find how high will it rebound after the first bounce when dropped from 10 ft. We can define the rebound ratio as shown below.
R = H_r/H_d
Here R is the rebound ratio, H_r is the height reached, and H_d is the height from where the ball is dropped. We can start solving this by finding the ball's rebound ratio from the information we know.
When dropped from 10 ft the Tennis ball should reach a height of 5.55 ft after the first bounce.
b We need to find how high the ball will rebound after the second bounce. From Part A we know that the height it reaches is obtained by H_r = R* H_d. Furthermore, we found that after the first bounce its height would be 5.55 ft. We can use the formula once more using 5.55 ft as the dropped height, to find the height it will reach after the second bounce.
The tennis ball will reach a height of 3.08 ft after the second bounce.
c We need to find how high the ball will rebound after the third bounce. From Part A we know that the height it reaches is obtained by H_r = R* H_d. Furthermore, we found in Part B that after the second bounce its height would be 3.08 ft. We can use the formula once more using 3.08 ft as the dropped height to find the height it will reach after the third bounce.
