14. You drop a ball from a height of 3 m, and it bounces back to a height of 1.4
ID: 1419942 • Letter: 1
Question
14. You drop a ball from a height of 3 m, and it bounces back to a height of 1.4 m (ignore air resistance) A) what fraction of its initial energy is lost during the bounce? B) what is the balls speed just as it leaves the ground after the bounce? C) where did the energy go? 14. You drop a ball from a height of 3 m, and it bounces back to a height of 1.4 m (ignore air resistance) A) what fraction of its initial energy is lost during the bounce? B) what is the balls speed just as it leaves the ground after the bounce? C) where did the energy go? A) what fraction of its initial energy is lost during the bounce? B) what is the balls speed just as it leaves the ground after the bounce? C) where did the energy go?Explanation / Answer
A) Initial energy = mgh = 3mg
Final energy = 1.4mg
fraction of lost energy =(3-1.4) /3 = 1.6/3 = 0.5333
B) v = sqrt(2gh)
=sqrt(2*9.8*1.4)
= 5.24 m/s
C) Energy has lost as heat into invironment.