UPSEE Solved Model Paper 4

KE = ½mv2
P = mv
Therefore, KE = ½(mv)2∕m = p2∕(2m)
Considering the mass to be constant, if the momentum is increased by 20%, let the new momentum be
P/ = P + 0.2P = 1.2P.
New kinetic energy, KE/ = (P/)2/(2m)
⇒ KE/ = (1.2)2[P2∕(2m)] = 1.44KE
⇒ (KE/)/KE = 1.44
⇒ (KE/ - KE)/KE = 0.44
⇒ (KE/ - KE)/KE × 100% = 44%