A 1 kg ball moving in some direction at 8 m/sec hits a 4 kg ball moving at 6 m/sec in the same direction. Assume that the 1 kg ball stops after collision. What will be the velocity, after collision, of the 4 kg ball if the 1 kg ball stops?
Correct answer: C. 8 m/sec
- A. 10 m/sec
- B. 0 m/sec
- C. 8 m/sec
- D. 12 m/sec
Explanation
Conservation of momentum: initial total = 1×8 + 4×6 = 8 + 24 = 32 kg·m/s. If 1 kg stops, all momentum transfers to 4 kg ball: v = 32/4 = 8 m/s.
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Displacement, velocity and acceleration describe motion, including the horizontal and vertical components of projectile motion. The chapter connects these quantities with Newton's laws, momentum and impulse, then applies conservation of momentum to collisions, distinguishing elastic collisions from inelastic ones.
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