Answer: 37.5 N.
- A 37.5 N
- B 40 N
- C 30 N
- D 50 N
Correct answer: A. 37.5 N
Explanation: T = 2m₁m₂g/(m₁+m₂) = 2·5·3·10/8 = 37.5 N.
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.