Question

A body started with a velocity of $20m{s}^{-1}$ and moving with an acceleration of $2m{s}^{-2}$. The distance (in $\text{m})$ travelled by the body in the $8^{th}$ second is

• A. $35$
• B. $20$
• C. $12$
• D. $10$

Answer 1

The correct option is A $35$

Given, $u=20m{s}^{-1},a=2m{s}^{-2},n=8$
As we know that, the distance travelled by the body in $n^{th}$ sec is given as
$S_n=u+\frac{1}{2}a(2n-1)$
$\Rightarrow S_n=20+\frac{1}{2}\times 2(2\times 8-1)$
$\Rightarrow S_n=20+(16-1)=20+15=35\text{m}$