A kg particle moving at m/s collides with a stationary kg particle and they coalesce. What is their common speed?
Answer and explanation
Correct answer: C. 2 m/s
- Step 1: Momentum before: kg m/s. Step 2. After: , so . Answer: 2 m/s. Why not the others: 3 m/s averages the two speeds, ignoring mass; 4 m/s takes the heavier mass fraction ( of 6); 6 m/s ignores the extra mass being carried.
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