Force is an external agent, which changes or tends to change the state, shape, acceleration or direction of motion of an object. • SI unit of force is Newton (N) while its CGS unit is dyne (1N=105dyne ) • 1 Newton Force: The force required to produce the acceleration of 1 m/s2 on a body of 1 kg mass is called one Newton force. i.e 1N= 1 Kg x 1mls2
Force Scalar Quantities: The physical quantities, which have a magnitude but no direction are called a scalar quantity. Mass, length, time, density, speed, work, work etc. are a few examples of scalars. • Vector Quantities: The physical quantities, which have both magnitudes as well as direction are called vectors quantities. Velocity, displacement, acceleration, force, momentum etc. are examples of vector quantities.