College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 24

A block that has a mass of 2.0 kg and is 10 cm wide on each side just begins to slide down an inclined plane with a 30° angle of incline (Fig.). Another block of the same height and same material has base dimensions of 20 cm × 10 cm and thus a mass of 4.0 kg. (a) At what critical angle will the more massive block start to slide down the plane Why (b) Estimate the coefficient of static friction between the block and the plane.

FIGURE At what angle will it begin to slide See Exercise.