Question

A body of mass $1kg$ is moving with a velocity $v=10\hat{i}+5\hat{j}$ m/s. What is the angle made by the momentum vector with $x-$ axis?

• A. ${\tan }^{-1}\frac{5}{2}$
• B. ${\tan }^{-1}\frac{1}{4}$
• C. ${\tan }^{-1}\frac{1}{2}$
• D. ${\tan }^{-1}\frac{3}{2}$

Answer 1

The correct option is C ${\tan }^{-1}\frac{1}{2}$


$\overrightarrow{p}=m\overrightarrow{v}=10\hat{i}+5\hat{j};$
$\tan \theta =\frac{y}{x}=\frac{5}{10}=\frac{1}{2}$
$⟹\theta ={\tan }^{-1}\frac{1}{2}$