Question

Question #96843

Answer 1

Alternately, one could simply calculate the impulse knowing the force and how long it is applied. The impulse is equivalent to the total change in momentum.

`I = Ft`

Impulse has units of Newton seconds.

`I = 6 * 6 = 36 Ns = 36 kgm/s`

We know that momentum is calculated from velocity as:
`P = mv`
So we can solve for the velocity.
`36 = 2*v`
`18 = v`

Using this velocity the kinetic energy can be calculated:
`E_k = 1/2mv^2`
`E_k = 1/2*2 * 18^2`
`E_k = 324 kgm^2/s^2`