Answer: mv*sqrt(2).
- A mv
- B mv*sqrt(2)
- C 2mv
- D 2mv/sqrt(2)
Correct answer: B. mv*sqrt(2)
Explanation: Only the perpendicular component reverses. Delta_p = 2 x mv x cos45 = mv*sqrt(2).
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.