Question

Part A If each box weighs 160 lb , determine the least horizontal force P that the man must exert on the top box in order to cause motion. The coefficient of static friction between the boxes is Ms = 0.80, and the coefficient of static friction between the box and the floor is M's = 0.25. (Figure 1) Express your answer with the appropriate units. μΑ ? re 1 of 1 P= Value Units -3 ft Submit Request Answer 4.5 ft < Return to Assignment Provide Feedback 5 ft 4.5 ft A B

Answer 1

Ms = 0.8 aft M's = 0.25 for Tipping of both Box about 4.5ft P B. PXS - 32x1.S=0 sft 4.5lt P = 96 lb. v SO for mohon P96 f' List 32016 F. BD of lower box f = frictional force between box 1 > Msx N' f 0.25% 320 f' = 80 lb f = f'= 80 lb 320 lb F. B.D of upper box Maximum frichonal ford on uppu box Iman = MSX N max P 0.8x160 = 128 lb • tmax - fa max creavired to move) to 160 lb do P. 11 । 80 16