A 2,537-kg truck moving at 14 m/s strikes a car waiting at a traffic light, hooking bumpers. The two continue to move together at 8 m/s. What was the mass (in kg) of the struck car

1902.75 kg

Explanation:

From Law of conservation of momentum,

m₁u₁ + m₂u₂ = V (m₁ + m₂) ... Equation 1

make m₂ the subject of the equation,

m₂ = (m₁V - m₁u₁) / (u₂-V) ... Equation 2

Where m₁ = mass of the truck, m₂ = mass of the car, u₁ initial velocity of the truck, u₂ = initial velocity of the car V = common velocity

Given: m₁ = 2537 kg, u₁ = 14, V = 8 m/s, u₂ = 0 m/s (as the car was at rest waiting at a traffic light)

Substituting into equation 2.

m₂ = [2537 (8) - 2537 (14) ] / (0-8)

m₂ = (20296-35518) / -8

m₂ = - 15222/-8

m₂ = 1902.75 kg.

Thus the mass of the car = 1902.75 kg