Question

The initial velocity of the particle is 10 $m\sec$ and its retardation is $2m/s^2$. The distance moved by the particle is 5th second of its motion is :

• A. $1m$
• B. $19m$
• C. $50m$
• D. $75m$

Answer 1

The correct option is A $1m$

Given,

$u=10m/s$

$a=-2m/s^2$

$n=5$

The distance covered by the particle in $n^{th}sec$

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

$S_5=10+\frac{-2}{2}(2\times 5-1)$

$S_5=10-9$

$S_5=1m$

The correct option is A.