Work Energy And Power Question 128
Question: A ball is allowed to fall from a height of 10 m. If there is 40% loss of energy due to impact, then after one impact ball will go up to [CPMT 1985]
Options:
A) 10 m
B) 8 m
C) 4 m
D) 6 m
Show Answer
Answer:
Correct Answer: D
Solution:
$ mgh= $ initial potential energy $ mg{h}’= $
final potential energy after rebound
As 40% energy lost during impact \mgh’=60% of mgh
therefore $ h’=\frac{60}{100}\times h=\frac{60}{100}\times 10=6m $
