Question

Define and state unit of (i) Displacement (ii) Velocity (iii) acceleration (iv) retardation

ICSE Class 9 Physics Chapter Motion in One Dimension

Answer 1

(i)Displacement-The displacement is the shortest distance between the first and the last positions of a body in a specified idrection. Its unit is"cm" in C.G.S system and "m" in S.I system.
(ii)Velocity: The velocity of a body is the distance travelled by it per unit time in a given direction. Its unit is "cm.s" in C.G.S system and "m/s" in S.I system.
(iii)Acceleration: Acceleration of a body is defined as the rate of change of its velocity with time(when velocity is increasing_.Its unit is "cm/s^2" in C.G.S system and "m/s^2" in S.I system
(iv) Retardation:Retardation or de-acceleration of a body is defined as the rate of change of its velocity with time(when velocity is decreasing).Its unit is "cm/s^2" in C.G.S System and "m.s^2" in S.I system.