Acar moving at 10.0 m/s crashes into a barrier and stops in 0.050 s. there is a 20.0-kg child in the car. assume that the child’s velocity is changed by the same amount as that of the car, and in the same time period. what is the impulse needed to stop the child?

The impulse needed to stop the child = -200 Ns

Explanation:

Impulse: This can be defined as the product of force and time of a body. The S.I unit of impulse is kgm/s or Ns

From newton's second law,

I = mΔv Equation 1.

Where I = Impulse needed to stop the child, m = mass of the child, Δ = change in velocity of the child.

Given: m = 20.0 kg,

Δv = v-u where v =0 m/s, u = 10.0 m/s

Δv = 0-10 = -10 m/s.

Substituting into equation 1

I = 20(-10)

I = -200 Ns.

Thus the impulse needed to stop the child = -200 Ns

Note: The negative sign shows that the impulse act against the motion of the child

graph question answered .. you think better when you are relaxed and happy

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.