Question

A particle initially at rest, moves with an acceleration $5m{s}^{-2}$ for $5s$. Find the distance traveled in $5th$ second.

• A. $45m$
• B. $25m$
• C. $22.5m$
• D. $62.5m$

Answer 1

The correct option is C $22.5m$

Distance traveled in 5th second = Distance traveled in $5s-$ Distance traveled in $4s$

Using $s=ut+\left(1/2\right)a{t}^2$

Distance traveled in 5 s $=\left(1/2\right)\times 5\times 5^2$

$=62.5m$

Distance traveled in 4 s $=\left(1/2\right)\times 5\times 4^2$

$=40m$

Distance traveled in 5th s $=\left(1/2\right)\times 5\times 5^2$

$=62.5m$$=S_2-S_1=(62.5-40)m=22.5m$