P5-47 5-48. The coefficient of friction between the 200-lb body A shown in Fig. P5-48 and the brake OD is 0.4, and between body A and the vertical plane it is 0.2. The coefficients of friction between the cord and the fixed drums B and C are 0.4 and 0.2, respec- tively. If the weight of the brake arm OD is negli- gible, determine the force P for which the impending motion of body A will be downward. 66 TITI

P5-47 5-48. The coefficient of friction between the 200-lb body A shown in Fig. P5-48 and the brake OD is 0.4, and between body A and the vertical plane it is 0.2. The coefficients of friction between the cord and the fixed drums B and C are 0.4 and 0.2, respec- tively. If the weight of the brake arm OD is negli- gible, determine the force P for which the impending motion of body A will be downward. 66 TITI

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.49P

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Principles ef Friction Tutovial 4 2507 4 m f 3 m a huvizuntal surtace and is acted as shoun alrove. Deter mnine the magnitude af tre force Fthat A 25 kg block rests on by an incline on farce will Cause the block to move. The coofsicentof friction between the two Contact surfaces is o.25. ANSWER: F= 69 N