Question

A car accelerates uniformly from 18 km/h to 36 km/h in 5 sec, calculate the acceleration.

• A. 1 $m{s}^{-2}$
• B. 3.6 $m{s}^{-2}$
• C. 2 $m{s}^{-2}$
• D. 2.6 $m{s}^{-2}$

Answer 1

The correct option is A 1 $m{s}^{-2}$

Given,

$u=18km/h=\frac{18\times 1000}{60\times 60}=5m/s$

$v=36km/h=\frac{36\times 1000}{60\times 60}=10m/s$

$t=5sec$

acceleration, $a=?$

1st equation of motion,

$v=u+at$

$10=5+5a$

$5a=5$

$a=\frac{5}{5}=1m/s$

The correct option is A.