Speed definition – Speed is defined as the rate at which a particle covers a distance along a given path. It is given by the ratio of distance travelled to the time taken. Speed formula – Distance travelled (s)/ Time (t) Note Since distance travelled is a scalar , the speed of a particle is also a scalar . The unit of speed is cm s -1 in C.G.S. system and m s -1 in M.KS. or S.I. system . Instantaneous Speed The speed of a particle at a given instant is known as instantaneous speed . The speedometer of a vehicle indicates the instantaneous speed of the vehicle . Uniform Speed : A body or particle is said to possess uniform speed if it travels equal distances in equal intervals of time. Consider a person travelling from A to B through O. If he walks at a constant rate of 1 m s -1 , i.e., for every 1 s if he travels 1 m, then the person is said to possess uniform speed. Uniform speed indicates that the instantaneous speed of particle r...