Question

A body starts from rest. What will be the ratio of the distance travelled by the body during the $4^{th}$ and $3^{rd}$ second?

• A. $7/5$
• B. $5/7$
• C. $7/3$
• D. $3/7$

Answer 1

The correct option is A $7/5$

We know that distance covered in $n^{th}$ second is given by the relation
$s_n=u+\frac{a}{2}(2n-1)$
Here,
$s_n$ = distance travelled in $n^{th}$ second.
$u$ = initial velocity of body
$a$ = acceleration
As started from rest $(u=0)$
$\therefore s_n\propto (2n-1)$
$\therefore \frac{s_4}{s_3}=\frac{7}{5}$