Question

If momentum is increased by 20% then kinetic energy increased by
A) 77%
B) 44%
C) 66%
D) 55%​

Answer 1

Answer:

1. the option B is the correct answer

Answer 2

Answer:

44%

Explanation:

Momentum is related to Kinetic energy as,

$\frac{p^2}{2m} = K.E$

Thus, we can say that,

K.E ∝ p²

Since, momentum is increased by 20%

New momentum = p + 0.2p = 1.2p

Thus,

$\frac{K.E_1}{K.E_2} = \frac{p^2}{1.44p^2}\\\\K.E_2 = 1.44K.E_1$

Therefore, percentage increase in kinetic energy

$\frac{K.E_2 - K.E_1}{K.E_1} *100 %\\\\=\frac{1.44-1}{1} * 100\\= 44%$

= 44%