When the force applied and the displacement of the body are inclined at 90º with each other, then work done isA infinite B maximum C unity D zero

When the force applied and the displacement of the body are inclined at 90º with each other, then work done isA infinite B maximum C unity D zero

In case of negative work, the angle between the force and displacement isA 0°  B 45°  C 90° D 180°

Work done is said to be positive when a force causes displacementA in its own direction  B in the direction opposite to the applied force C in the direction at right angles to the direction of applied force  D none of the above

A force F at an angle 𝜃𝜃 above the horizontal is used to pull a heavy suitcase of weight mg a distance d along a level floor at constant velocity. The coefficient of friction between the floor and the suitcase is 𝜇𝜇. The work done by the frictional force is:

When an angle between parallel and perpendicular exists between the applied force and direction of motion, the work done is than the product of force and distance and than zero.