Question

A body constrained to move in the y-direction, is subjected to a force $\overrightarrow{F}=-6\hat{i}+8\hat{j}N$. The work done by this force in moving the body a distance of $10m$ along y-axis is :

• A. $100J$
• B. $140J$
• C. $80J$
• D. $20J$

Answer 1

Answer: (C)

$80J$

Work done $=\overrightarrow{F}\cdot \overrightarrow{r}=(-6\hat{i}+8\hat{j})\cdot \left(10\hat{j}\right)=80J$