A particle starting from rest. Its acceleration (a) versus time (t) is as shown in the figure.
The maximum speed of the particle will be.

Options

A. `110 ms^(-1)`
B. `55 ms^(-1)`
C. `550 ms^(-1)`
D. `660 ms^(-1)`

Answer

B

Explanation

Till 11s, acceleration is positive, so velocity will go on increaseing up to 11 s and maximum velocity will happened at 11s. The area under the acceleration -time graph gives change in velocity. Since particle starts with `u = 0`, change in velocity is
`v_(f) - v_(i) = v_("max") - 0 =` Area under `a - t` graph
or `v_("max") = (1)/(2) xx 10 xx 11 = 55 ms^(-1)`