Question

define displacement and gives it SI unit. when acceleration of a body negative? Give two examples of situations in which acceleration of a body is negative.

Answer 1

Displacement is the shortest distance between any two points( or two places).
It's S.I. unit is same as distance,i.e., m/s
Two examples from daily life when acceleration is negative :-
1. When u applies brake to a bicycle then acceleration is negative
2.When a ball is thrown vertically upward, then the acceleration of the ball is negative.
Note:- When acceleration is negative(or u can say negative acceleration), then it is also termed as retardation.
It means retardation is the negative acceleration