Question

A 1400 kg car moving +13.7 m/s makes an elastic collision with a 3200 kg truck, initially at rest. What is the velocity of the car after the collision?

Answer 1

The velocity of the car after the collision is -5.36 m/s

Explanation:

An elastic collision is an encounter between two bodies in which the total kinetic energy of the two bodies remains the same.

let the following:

m₁ = mass of the car = 1400 kg

m₂ = mass of the truck = 3200 kg

u₁ = velocity of the car before collision = 13.7 m/s

u₂ = velocity of the truck before collision = 0 m/s

v₁ = velocity of the car after collision

v₂ = velocity of the truck after collision

v₁ = [ u₁ * (m₁ - m₂) + u₂ * 2m₂ ]/ (m₁ + m₂)

= [ 13.7 * (1400 - 3200) + 0 * 2 * 3200 ]/ (1400 + 3200)

= - 5.36 m/s

So, the velocity of the car after the collision is -5.36 m/s