Question

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

• A. $1\text{m}$
• B. $19\text{m}$
• C. $50\text{m}$
• D. $75\text{m}$

Answer 1

The correct option is A $1\text{m}$

As we know that the distance travelled by a particle in $n^{th}$ second is given as
$S_n=u+\frac{a}{2}(2n-1)$
Given, $u=10\text{m/s},a=-2{\text{m/s}}^2$
$\Rightarrow S_{5^{th}}=10-\frac{2}{2}(2\times 5-1)=1\text{meter}$