Question

Electrical potential `V` in space as a function of co-ordinates is given by `,V=(1)/(x)+(1)/(y)+(1)/(z)`
then the electric field intensity at `(1,1,1)` is given by:
A. `hati+hatj+hatk`
B. `hati+hatj-hatk`
C. `hati-hatj+hatk`
D. `-hati+hatj+hatk`

Answer 1

Correct Answer - B
`V=(1/x+1/y+1/z)`
`vec(E)=-(delV)/(delx) hati-(delV)/(dely) hatj-(delV)/(dz) hatk=1/(x^(2)) hati+1/(y^(2)) hatj+1/(z^(2)) hatk`
`:. vec(E)(1,1,1)=hati+hatj+hatk`