1 2 3. 4 The force required just to move a body up i inclined plane is double the force required just to prevent the body sliding down. If the coefficient of friction is 0.25, the angle of inclination of the plane a) 37 @ 45° 3) 30° 4) 53° A body is projected up a 45° rough incline. If the coefficient of friction is 0.5, then the retardation of the block is yn oy 8 © 38 oR 3g 8 gy 38 a) £ @ 8 O43 A rope lies on a table such that a part of it hangs down the table, When the length of hanging part is 1/3 of entire length the rope just begins to slide. The coefficient of friction between the rope and the table is: a) 28 @Q) W2 @) 1B 4) 6 Figure shows a block kept on a rough inclined plane ‘The maximum external force down the incline for which, the block remains at rest is 1 N while the maximum external force up the incline for which the block is at rest is 7N. The coefficient of static friction yw 30° a) & ole @) 5 A block of mass m is at rest relative to the stationary wedge of mass M. The coefficient of friction between block and wedge is jt. The wedge is now pulled horizontally with acceleration ‘a’ as shown in figure, Then the minimum magnitude of ‘a’ for the friction between block and wedge to be zero is: | © aN @ gtand 2) ng tan @ geod @) ng cot Starting from rest, a body slides down a 45° inclined plane in twice the time it takes to slide down the same distance in the absence of friction. ‘The coefficient of friction between the body and the inclined plane is @ 033 @) 025 @) 0.75 0.80 A mass of 5 kg is placed on a horizontal rough surface. Coefficient of friction between body and surface is 0.5. The minimum horizontal force with which the block can just able to move is (Take g = 10 m/s*) Ske n= 08 @) 25N @ (50) +(257 GB) SON 4) 225N A body of mass 2 kg is released on an inclined plane as shown in figure, Acceleration of the body down the plane is n=08 70 () 6 ms? @ GB) 38m? @ 2.3 m/s?10. A block of mass 5 kg resting on a horizontal surface is connected by a cord, passing over a light frictionless pulley to a hanging block of mass 5 kg. ‘The coefficient of kinetic friction between the block and the surface is 0.5. Tension in the cord is (@=98 mi’) A kg SB () 49N (2) Zero G3) 36.75N (4) 12.75 ‘A system consists of three masses mi, mz and ms connected by a string passing over a pulley P, The mass mm hangs freely m2 and m3 are on a rough horizontal table (the coefficient of friction = j2). The pulley is frictionless and is of negligible mass. The downward acceleration of mass mt i (Assume mi = 1. = m3 = m) 1. © ZL Am, @ as 2 2a g(l-2u) 2-2) o o A block B is pushed momentarily along a horizontal surface with an initial velocity v, if pis the coefficient of sliding friction between B and the surface, block B will come to rest after a time: a Ly dQ) wen 2) shiv @) gv 4) vg