Question
Sun March 04, 2012 By:
 

A ball is dropped from a height of 10m. If the energy of the ball reduces by 40% after striking the ground. How much high can the ball bounce back?

Expert Reply
Sun March 04, 2012

H1 =10 m, v1 =?

Loss of energy =40% H2 =?

On striking the floor , K.E = P.E

½ mv12 = mg H1

V1 = ?(2gH1)= ?( 2x9.8x10)

 V1= ?196= 14 m/s

 As the body loses 40% of its energy , final energy E2 =( 60/100) of initial energy

i.e. mgH2 = (60/100)mgH1

H2 =3/5 H1= (3/5)X10= 6m

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