Question

A ball of mass 5 kg moving with speed 8 m/s collides gwad on with another stationary ball of mass 15kg if the collision is perfectlyinelastic then lost in kinetic energy

Answer 1

Explanation:

◆ Answer-

120 J

◆ Explaination-

# Given-

m1 = 5 kg

u1 = 8 m/s

m2 = 15 kg

u2 = 0

# Solution-

According to law of conservation of momentum-

m1u1 + m2u2 = (m1+m2)v

5×8 + 15×0 = (5+15)v

v = 40/20

v = 2 m/s

Initial kinetic energy -

KEi = 1/2 m1u1^2 + 1/2 m2u2^2

KEi = 0.5×5×(8)^2 + 0.5×15×(0)^2

KEi = 160 J

Final kinetic energy -

KEf = 1/2 (m1+m2)v^2

KEf = 0.5 × (5+15) × 2^2

KEf = 40 J

Loss of kineic energy-

∆KE = KEi - KEf

∆KE = 160 - 40

∆KE = 120 J

Therefore, loss of kinetic energy in given inelastic collision is 120 J.