Question

A body starts from the rest with uniform acceleration. If its displacement in the 3rd seconds and 7th second are $x_1$ and $x_2$, then:

• A. $13x_1=5x_2$
• B. $5x_1=13x_2$
• C. $3x_1=7x_2$
• D. $7x_1=3x_2$

Answer 1

Answer: (A)

$13x_1=5x_2$

$s_n$ is the distance covered in $nth$ sec

$s_n=u+\frac{a}{2}(2n-1)$

$u=0$

$\frac{x_1}{x_2}=\frac{2\times 3-1}{2\times 7-1}$

$13x_1=5x_2$