Answer: sqrt(50) m/s.
- A 5 m/s
- B sqrt(50) m/s
- C 10 m/s
- D 20 m/s
Correct answer: B. sqrt(50) m/s
Explanation: Minimum speed at top: v = sqrt(gR) = sqrt(10 x 5) = sqrt(50) approx 7.07 m/s.
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.