Question

A car starts from rest and uniformly accelerates in a straight line. In the first second the car covers a distance of $2$ m. The velocity of the car at the end of $2^{nd}$ $second$ will be

• A. $4.0m{s}^{-1}$
• B. $8.0m{s}^{-1}$
• C. $6m{s}^{-1}$
• D. None of these

Answer 1

The correct option is B $8.0m{s}^{-1}$

distance covered by car in t seconds$=0\ast t+\frac{1}{2}a{t}^2$
for $t=1$ distance is 2m.
$2=\frac{1}{2}a\ast 1^{2}a=4m/s^2$
velocity after 2 seconds.
$v=u+at=0+4\ast 2=8m/s$