Question

A force F = (5î + 3ĵ) newton is applied over a particle which displaces it from its origin to the point r = (2î − 1ĵ) metres. The work done on the particle is

A particle is acted upon by a force of constant magnitude, which is always perpendicular to the velocity of the particle, the motion of the particle takes place in a plane. It follows that

Assertion: A person working on a horizontal road with a load on his head does no work. Reason: No work is said to be done, if directions of force and displacement of load are perpendicular to each other.

(a) Define work done. How can we calculate work done by (i) Constant force (ii) Variable force and (iii) From graph if an object is displaced along a straight line. (b) Find work done by a force F = 2x (SI unit) if it displaces an object from origin to a Point (1, 2,-2)