Question

A body starting from rest moving with uniform acceleration has a displacement of $16\text{m}$ in first $4\text{s}$ and $9\text{m}$ in first $3\text{s}$. the acceleration of the body is

• A. $1{\text{ms}}^{-2}$
• B. $2{\text{ms}}^{-2}$
• C. $3{\text{ms}}^{-2}$
• D. $4{\text{ms}}^{-2}$

Answer 1

The correct option is B $2{\text{ms}}^{-2}$

Distance travelled in $4^{th}$ second $=16-9=7\text{m}$
Now $D_n=u+\frac{a}{2}(2n-1)$, Given $u=0$
$\Rightarrow 7=0+\frac{a}{2}(2\times 4-1)\Rightarrow a=2{\text{m/s}}^2$