A bus moving along a straight line at $20\ m/s$ undergoes an acceleration of $4\ m/s^2$. After 2 seconds, its speed will be:
(a) $8\ m/s$
(b) $12\ m/s$
(c) $16\ m/s$
(d) $28\ m/s$

Academic Physics NCERT Class 9

Here initial velocity $u=20\ m/s$

Acceleration $a=4\ m/s^2$

Time $=2\ s$

On using the first equation of motion, $v=u+at$

$v=20+4\times2$

Or $v=28\ m/s$

So, option (d) is correct.

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Updated on: 10-Oct-2022

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