The velocity-time graph of a body is given below. Find the average velocity from `t = 0` to `t = 40 s`.

Options

A. `20 m//s`
B. `40 m//s`
C. `50 m//s`
D. `60 m//s`

Answer

A

Explanation

Displacement = area upto `t = 40 s`
=`(1)/(2) xx 20 xx 20 +(30 - 20) xx 20`
`+ (1)/(2)[20 + 60][40 - 30] = 800 m`
:. `v_(av) = ("Displacement")/("time") = (800)/(40) = 20 m//s`.