Q3) The three flat blocks are positioned on the 30° incline as shown, and a force P parallel to the incline is applied to the middle block. The upper block is prevented from moving by a wire which attaches it to the fixed support. The coefficient of static friction for each of the three pairs of mating surfaces is shown. Determine the maximum value which P may have before any slipping takes place. 30 kg 50 kg 40 kg H.-0.45 H₂0.30 P 1,-0.40 30 Fig.(Q).

Q3) The three flat blocks are positioned on the 30° incline as shown, and a force P parallel to the incline is applied to the middle block. The upper block is prevented from moving by a wire which attaches it to the fixed support. The coefficient of static friction for each of the three pairs of mating surfaces is shown. Determine the maximum value which P may have before any slipping takes place. 30 kg 50 kg 40 kg H.-0.45 H₂0.30 P 1,-0.40 30 Fig.(Q).

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 7.17P: The two uniform sheets of plywood, each of length L and weight W, are propped as shown. If the...

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The two uniform sheets of plywood, each of length L and weight W, are propped as shown. If the coefficient of static friction is 0.5 at all three contact surfaces, determine whether the sheets will remain at rest.
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The blocks A and B of weights WA and WB are joined by a rope that passes over the fixed peg C. The coefficients of static friction are =0.2 between block A and the inclined plane, and =0.25 between the rope and the peg. Determine the range of Wb/WA for which the system will be in equilibrium.
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