Question

The kinetic energy of an object with a mass of `2 kg` constantly changes from `32 J` to `84 J` over `4 s`. What is the impulse on the object at `1 s`?

Answer 1

`F*Delta t=2,1" " N*s`

Explanation:

`tan theta=(84-32)/4`

`tan theta=52/4=13`
`E=1/2*m*v^2" "v^2=(2E)/m" ; "v=sqrt((2E)/m)" ; "v=sqrtE`
`t=0" "E=32J" "v=5,66m/s`
`t=1" "E=32+13=45J" "v=6,71m/s`
`t=2" "E=45+13=58J" "v=7,62m/s`
`t=3" "E=58+13=71J" "v=8,43m/s`
`t=4" "E=71+13=84J" "v=9,17m/s`

`"impulse for t=1 "`
`F*Delta t=m(v(1)-v(0))`

`F*Delta t=2(6,71-5,66)`
`F*Delta t=2*1,05`
`F*Delta t=2,1" " N*s`