A particle starts from rest at ` t= 0` and undergoes and acceleration (a) in `ms^(-2)` with time (t) in seconds which is shown in Fig. 2 (DF) .16 . Which one of the following plot represents velocity (v) (in `ms^(-1)`) verses time (in seconds ) ?

Options

A.
B.
C.
D.

Answer

A

Explanation

t = 0 to 2 sec
u = 0`, a=3 m//s^2`
`rArr v = u + at = 3 xx2 = 6m//s`
Now, t = 2 to 4 second
`v = 6 - 3 xx 2 = 0m//s`
`a = 3, 0 lt t lt 2`
` = -3, 2 lt t lt 4`