A gardener moves a lawn roller through a distance of 50 m with a force of 100N. If the force is acting at an angle of 60° to the direction of motion, find the work done.

A body of mass 15 kg is moving with a velocity 20 m/s. Calculate the distance travelled by the body before stopping, if a force of 30 N is applied on the body in the direction opposite to the direction of motion.

An object thrown at a certain angle to the ground moves in a curved path and fails back to the ground.. The initial and the final points of the path of the object lie on the same horizontal line. What is the work done by the force of gravity on the object?

A force of 7 N acts on an object. The displacement it, say 8m, in the direction of the force. Let us take it that the force acts on the object through the displacement. What is the work done in this case?

A proton moving with velocity (10^7) m/s to enters a magnetic field of 1.5 T making an angle 30° with the direction of the field. Find the radius of the helical path and its frequency of rotational motion

The angle of elevation of the top of a tower at a point on a level ground is 30°.After walking a distance of 100mtowards the foot of the tower along the horizontal line through the foot of the tower on the same level ground, the angle of elevation of the top of the tower is 60°.Find the height of the tower.

A body of mass 2 kg initially at rest moves under the action of 0 an applied horizontal force of 7 N on a table with coefficient of kinetic friction= 0.1. Compute the (a) work done by the applied force in 10 s, .

A body of mass 2 kg initially at rest moves under the action of 0 an applied horizontal force of 7 N on a table with coefficient of kinetic friction= 0.1. Compute the work done by friction in 10 s,

Calculate the work done in rotating a magnet of pole strength [10^(-2)] Ampere-m and magnetic length 10 cm through an angle of 60° from its position along the magnetic, meridian. (B = 200T)

A rain drop of radius 2 mm falls from a height of 500 m above the ground. It falls with decreasing acceleration (due to viscous resistance of the air) until at half its original height, it attains its maximum (terminal) speed, and moves with uniform speed thereafter. What is the work done by the gravitational force on the drop in the first and second half of its journey? What is the work done by the resistive force in the entire journey if its speed on reaching the ground is 10 m s-^1 ?

Two straight wires A and B of lengths 10 m cach carrying currents of 4.0 A and 6.0 A in opposite directions lic parallel to each other at a distance of 2 cm. Estimate the force on a 10 cm section of the wire B near its centre.