A particle moving with variable velocity is said to possess acceleration. When a particle executes non-uniform motion, its velocity changes. Acceleration is defined as the rate of change of velocity . It is a vector quantity. Unit of acceleration SI unit of acceleration metre per second per second (m s -2 ) and cgs unit of acceleration cm s -2 . By definition, acceleration, \(\vec{a}\) = change in velocity/Time = \(\vec{v}\)-\(\vec{u}\)/t ExampleA car moves along a straight path with variable velocity as shown in the figure. When the car is at position A, its velocity is 10 m s −1 and when it is at position B, its velocity is 20 m s −1 . If the car takes 5 seconds of time to move from A to B, find the acceleration of the car. SolutionInitial position of the car at position A = u = 10 m s −1 Final velocity of the car at position B = v = 20 m s −1 The change in velocity of the car, Δv = v = 20 m s −1 −10m s −1 = 10 m s −1 The time taken for the car to move from A to B, Δt...