Previous Year NEET Question- Laws Of Motion L-9
Question:
A force on an object of mass $100 \mathrm{~g}$ is $(10 \hat{i}+5 \hat{j}) \mathrm{N}$. The position of that object at $\mathrm{t}=2 \mathrm{~s}$ is ${ }^{(a \hat{i}+b \hat{j})} \mathrm{m}$ after starting from rest. The value of $\mathrm{a} / \mathrm{b}$ will be
Answer:
$\begin{aligned} & \vec{F}=m \vec{a} \ & \Rightarrow \vec{a}=100 \hat{i}+50 \hat{j} \ & \text { So, } \vec{S}=\frac{1}{2} \vec{a} t^2 \ & \frac{1}{2}(100 \hat{i}+50 \hat{j}) (2)^2 \ & =200 \hat{i}+100 \hat{j} \mathrm{~m} \ & \text { so } \mathrm{a}=200 \mathrm{~m} \text { and } \mathrm{b}=100 \mathrm{~m} \ & \text { so } \frac{a}{b}=2\end{aligned}$