Answer: Zero.
- A Double the initial speed
- B Same as initial speed
- C Half the initial speed
- D Zero
Correct answer: D. Zero
Explanation: Total momentum = mv - mv = 0. After sticking: (2m) v<sub>f</sub> = 0, so v<sub>f</sub> = 0.
Free-body diagram of a block on an incline: weight (mg) resolves into mg sinθ along the slope and mg cosθ into the slope, balanced by the normal force N and friction f.
Concept context
Newton's three laws, friction, circular motion, and free body diagrams.