Cart A (mass 3 kg) moves at 4 m/s and collides elastically with stationary Cart B (mass 3 kg). After the collision, Cart A is at rest. What is Cart B's velocity?

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Question

Cart A (mass 3 kg) moves at 4 m/s and collides elastically with stationary Cart B (mass 3 kg). After the collision, Cart A is at rest. What is Cart B's velocity?

Accepted Answer

4 m/s — Using conservation of momentum: (3)(4) + (3)(0) = (3)(0) + (3)v_B → 12 = 3v_B → v_B = 4 m/s. In an elastic collision between equal masses, all velocity transfers to the second object. Option A incorrectly splits velocity equally. Option B multiplies mass by velocity incorrectly. Option D divides initial momentum by total mass as in an inelastic collision.

Answer

12 m/s

Answer

2 m/s

Answer

1.3 m/s

Answer

4 m/s

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