A block f mass M is held against a rough vertical wall by pressing it with a finger. If the coefficient of friction between the block and the wall is `mu` and the acceleration due to gravity is g. calculate the minimum force required to be applied by the finger to hold the block against the wall?

A rectangular box lies on a rough incli ned surface. The co-efficient of friction between the surface and the box is mu. Let the mass of the box is be m. What is the force needed to be applied upwards along the plane to make the box move up the plane with acceleration alpha ?

A 70 kg man stands in contact against the ineer wall of a hollow cylindrical drum of radius 3 m rotating about its vertical axis with 200 rev//min . The coeffcient of friction between the wall and his clothing is 0.15. What is the minimum rotational speed of the cylinder to enable the man of remain stuck to the wall ( without falling) when the floor ids suddenly removed?

What is the acceleration of the block and trolley system shown in the figure, if the coefficient of kinetic friction between the trolley and the surface is 0.04?/ What is the tension in the string? (Take g = 10 ms^-2 ) Neglect the mass of the string.

A block of mass 1 kg is pushed up a surface inclined to horizontal at ang angle of 30^@ by a force of 10 N parallel to the inclined surface in the figure. shows . The coefficient of friction between bock and the incline is 0.1. If the block is pushed up by 10 m along the incline, calculate work done against gravity

A block of mass 1 kg is pushed up a surface inclined to horizontal at ang angle of 30^@ by a force of 10 N parallel to the inclined surface in the figure. shows . The coefficient of friction between bock and the incline is 0.1. If the block is pushed up by 10 m along the incline, calculate work done against force of friction

A block of mass 1 kg is pushed up a surface inclined to horizontal at ang angle of 30^@ by a force of 10 N parallel to the inclined surface in the figure. shows . The coefficient of friction between bock and the incline is 0.1. If the block is pushed up by 10 m along the incline, calculate work done by applied force.

Two bodies A and B of masses 5 kg and 10 kg in contact with each other rest on a table against a rigid wall (Fig. 5.21). The coefficient of friction between the bodies and the table is 0.15. A force of 200 N is applied horizontally to A. What are :- the reaction of the partition.

A block of mass 1 kg is pushed up a surface inclined to horizontal at ang angle of 30^@ by a force of 10 N parallel to the inclined surface in the figure. shows . The coefficient of friction between bock and the incline is 0.1. If the block is pushed up by 10 m along the incline, calculate increase in potential energy

A 1 kg block situated on a rough incline is connected to a spring of spring constant 100N m^-1 as shown in Fig. 6.17. The block is released from rest with the spring in the unstretched position. The block moves 10 cm down the incline before coming to rest. Find the coefficient of friction between the block and the incline. Assume that the spring has a negligible mass and the pulley is frictionless.