A force of 5 kgfis just sufficient to pull a block of weight 8 kgf over a horizontal surface. Find the angle of friction.

A force of 3 kg weight is just sufficient to pull a block of 4 kg over a horizontal surface.What is the angle of friction?

A force of 50 kg is requird to pull a roller weighing 500 kg over ice.What is ceofficient of friction?

A block is pushed by a force F = 10 N. A frictional force of 2 N acts between the block and the surface. Find the work done by the friction when the block moves 10 m.

A 8,000 kg engine pulls a train of 5 wagons, each of 2,000 kg along a horizontal track. If the engine exerts a force of 40,000 N and track offers a force of friction of 5,000 N, then calculate the :force of wagon 1 on wagon 2.

A 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of 5000 N, then calculate: the acceleration of the train.

A circular coilof radius 0.157 m has 50 number of turns. It is placed such that its axis is in magnetic meridian. A dip needle is supported at the centre of the coil with its axis of rotation horizontal, and in the plane of the coil. The angle of dip is 30^(@) when a current flows through the coil. The angle of dip becomes 60^(@) on reversing the current. Find the current in the coil assuming that the magnetic field due to the coil is smaller than the horizontal component of earth's magnetic field, H =3xx10^(-5) T.