Acceleration - time graph of a particle moving in a straight line is shown in figure. Velocity of particle at time t = 0 is `2 ms^(-1)`. Find velocity at the end of fourth second.

Explanation

According to acceleration time - graph, dv = s dt
or change in elocity = area under a - t graph
Hence, `v_(f)-v_(i)=(1)/(2)(4)(4)=8 ms^(-1)`
`therefore v_(f)=v_(i)+8=(2+8)ms^(-1)=10 ms^(-1)`