A body of mass 5 kg is moving with a momentum of 10 kg ms^(-1). A force of 0.2 N acts on it in the direction of motion of body for 10 s. The increase in its kinetic energy is

A body of mass 5 kg is moving with a momentum of 10 kg ms^(-1). A forc

1.	A body of mass 5 kg is moving with a momentum of 10 kg ms^(-1). A force of 0.2 N acts on it in the direction of motion of body for 10 s. The increase in its kinetic energy is
Answer» 2.8 J 3.2 J 3.8 J 4.4 J Solution :Initial kinetic ENERGY = `(p_1^2)/(2M) = (10 xx 10)/(2 xx 5) = 10 J` Impulse = `p_2 - p_1 = F xx t` `:. p_2 - 10 = 0.2 xx 10 or p_2 = 12 kg ms^(-1)` Final kinetic energy = `(p_2^2)/(2m) = (12xx 12)/(2 xx 5) = 14.4 J` INCREASE in kinetic energy = `14.4 J - 10 J = 4.4 J`