Answer: Yes, slips.
- A Yes, slips
- B No, does not slip
- C Cannot determine
- D Only if force > 20 N
Correct answer: A. Yes, slips
Explanation: Friction available on upper block = 0.4 x 3 x 10 = 12 N. Max a = 12/3 = 4 m/s<sup>2.</sup> System a = 10/5 = 2 m/s<sup>2.</sup> Force on upper = 3 x 2 = 6 N < 12 N, so no slip. Correct is: does NOT slip.
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.