Question

Problem 4 In a lab experiment, a cart of mass 2 kg, moving initially to the right at 3 m/s, collides head-on with a cart of unknown mass, moving initially to the left at 2 m/s. As a result of the collision, the carts bounce back with exactly the opposite velocity of what they had going in. Assume the system is effectively isolated (a)What is the mass of the second cart? (b)What is the total momentum of the system? (c)What is the velocity of the system's center of mass? d)Describe the collision (initial and final velocities) from the perspective of an inertial observer that is moving throughout to the right at 3 m/s

Answer 1

m_1 = 2 kg, v_1 = 2 m/s, m_2, v_2 = -2 m/s v_1 = -3 m/s, v_2 = 2 m/s Conservation of Momentum 2(3) + m_2 (-2) = 2(-3) + m_2(-2) 6 - 2m_2 = -6 + 2m_2 4m_2 = 12 m_2 = 3 kg Total momentum of system = m_1 v_1 + m_2 v_2/m_1 + m_2 = 0 Initial velocity of m_1 wrt observes u_1 prime = 3 - 3 = 0 m/s u_2 prime = 3 + 2 = 5 m/s Initial velocities Final velocities, v_1 prime = -3 - 3 = -6 m/s v_2 prime = 2 - 3 = -1 m/s