Question

Kinetic energy of body is increased by 300 % momentum of body is increased by?

Answer 1

Momentum increased to double, an increase of 100%.

Explanation:

Assume the increase is because of increase in speed (instead of increase in mass -- a bit hard to imagine how that would happen).

If initial KE was `KE_i` and KE was increased by 300% it is now

`KE_i + 3*KE_i = 4*KE_i`.

The formula for KE is

`KE = 1/2*m*v^2`

Since we assume the only parameter that changed was the velocity, the final velocity is 4 X the initial velocity. Therefore the final velocity is

`v_f = sqrt(4*v_i^2) = 2*v_i`

Since momentum is m*v,

the original momentum was `m*v_i`.

Since the final velocity is `2*v_i`,

final momentum is `m*2*v_i`

Momentum increased to double, an increase of 100%.

I hope this helps,
Steve