Question

A 1500 kg car hits a haystack at 8m/s and comes to a stop after 0.6 seconds

A)what is the change in momentum of the car ?
B) what is the impulse that acts on the car ?
C) what is the average force that acts on the car during the collision?
D) what is the work done by the haystack in stopping the car ?

Answer 1

Kindly check explanation

Step-by-step explanation:

Change in momentum:

m(v - u)

M = mass = 1500kg

v = final velocity = 0 m/s

u = initial velocity = 8m/s

Momentum = 1500(8 - 0)

Momentum = 1500 * 8

Momentum = 12000 kgm/s

B.) impulse that acts on the car

Impulse = Force * time

Impulse = change in momentum with time

Impulse = m(v - u)

Hence, impulse = 12000Ns

C.) Average force action on the car during collision

Impulse = Force * time

12000 = force * 0.6

12000/ 0.6 = force

Force = 20000 N

D.) Workdone by haystack in stopping the car :

Workdone = Force * Distance

Distance = speed * time

Distance = 8 * 0.6

Distance = 4.8m

Hence,

Workdone = 20,000 * 4.8 = 96000 J