Question

Gravitational field in a region is given by vector $(4\hat{i}+\hat{j})$. Work done by this field is zero when particle is moved along line.

• A. $y+4x=2$
• B. $4y+x=6$
• C. $x+y=4$
• D. $x-y=4$

Answer 1

The correct option is A $y+4x=2$

Vector along line $y+4x=2$ is $-\hat{i}+4\hat{j}$

So $(-\hat{i}+4\hat{j}).(4\hat{i}+\hat{j})=0$