Question

A bumper car with a mass of 250 kg is traveling at a speed of 4 m/s. This bumper car collides and sticks to a second bumper car with a mass of 250 kg, which is initially at rest. What is the final speed of these two bumper cars after the collision, assuming they remain stuck together?

Answer 1

Here in this type of collision problem we can say that there is no external force on the system of two cars

So we can use the momentum conservation in this

$m_1v_{1i} + m_2v_{2i} = m_1v_{1f} + m_2v_{2f}$

here we have

$m_1 = m_2 = 250 kg$

$v_{1i} = 4 m/s$

$v_{2i} = 0$

$v_{1f} = v_{2f} = v$

now from above equation we will have

$250 (4 m/s) + 0 = 250 v + 250 v$

$1000 = 500 v$

$v = 2 m/s$

so both cars will move together with speed 2 m/s