Question

A car which has an initial velocity of 4 m/s accelerates at the rate of $2{\text{m/s}}^2$ for 5 seconds. What will be its final velocity and the distance that it covers in these 5 seconds ?

• A. $12\text{m/s}$ and $40\text{m}$
• B. $14\text{m/s}$ and $45\text{m}$
• C. $10\text{m/s}$ and $45\text{m}$
• D. $14\text{m/s}$ and $40\text{m}$

Answer 1

The correct option is B $14\text{m/s}$ and $45\text{m}$

$u=4\text{m/s},a=2{\text{m/s}}^2,t=5s$
$v=u+at=4+2\times 5=14\text{m/s}$
$s=ut+\frac{1}{2}a{t}^2=4\times 5+\frac{1}{2}\times 2\times 5^2=20+25=45\text{m}$.
Hence the correct option is (b).