Question

Object A with a mass of 500 kilograms hits stationary object B with a mass of
920 kilograms. If the collision is elastic, what happens after the collision?

Answer 1

Both objects move away from the site of the collision, with speeds
and in directions such that the total kinetic energy and vector-momentum
of both of them are equal to the total kinetic energy and vector-momentum
that Object-A had before the collision.

Answer 2

Answer:

Both objects will move

Explanation:

The collision is elastic, which means that both the total momentum and the total kinetic energy will be conserved after the collision. Therefore, we will have:

$m_A u_A = m_A v_A + m_B v_B\\\frac{1}{2}m_A u_A^2 = \frac{1}{2}m_A v_A^2 + \frac{1}{2}m_B v_B^2$

where the first equation represents the conservation of the total momentum, while the second equation represents the conservation of the kinetic energy, and

$u_A$ is the velocity of object A before the collision

$v_A$ is the velocity of object A after the collision

$v_B$ is the velocity of object B after the collision

$m_A = 500 kg, m_B=920 kg$ are the masses of the two objects.