An object of mass 10 kg moving with a speed of `15 ms^(-1)` hits the wall and comes to rest within
a) 0.03 second
b) 10 second
Calculate the impulse and average force acting on the object in both the cases.

Explanation

Initial momentum of the object `p_(i)=10xx15=150 kg ms^(-1)`
Final momentum of the object `p_(f)=0`
`Delta p=150-0=150 kg ms^(-1)`
(a) Impulse `j= Delta p=150 Ns`
(b) Impulse `j= Delta p=150 Ns`
Average force `F_(org)=(Delta p)/(Delta t)=(150)/(0.03)=5000 N`
(b) Average force `F_(org)=(150)/(10)=15N`
We see that, impulse is the same in both cases, but the average force is different.