Question

A person runs $40m$ to the north in $6.0s$, and then $30m$ to the east in $4.0s$. Find out the average velocity of the person?

• A. $5.0m/s$
• B. $6.0m/s$
• C. $6.7m/s$
• D. $7.0m/s$
• E. $7.5m/s$

Answer 1

The correct option is A $5.0m/s$

Displacement of the person $\overrightarrow{S}=40\hat{j}+30\hat{i}$

$⟹$ $|\overrightarrow{S}|=\sqrt{(30{)}^2+(40{)}^2}=50$ m

Total time taken $t=6+4=10$ s

$⟹$ Average velocity $v_{avg}=\frac{|\overrightarrow{S}|}{t}=\frac{50}{10}=5.0$ $m/s$