Question

On the axis of a short electric dipole at a point potential is V.If the dipole is rotated through 90° potential at same point is​

Answer 1

Explanation:

When a dipole AB of very small length is taken, then for a point P located at an axial distance r from the axis the electric field is given by

E=

4πε

0

1

r

3

2P

...(i)

When dipole is rotated by 90

o

, then electric field is given by

E

′

=

4πε

0

1

r

3

P

...(ii)

From Eqs. (i) and (ii), we get

E

′

=

2

E

Answer 2

The potential is zero.

Given:

The potential is V at some point where the angle is θ

To Find:

The potential at the same point when the angle, θ is 90°.

Solution:

If the dipole is rotated through 90°, then the angle θ becomes 90

we know,

Potential, V = kpcosθ/ r²

                    = 0                      (∵cos 90° = 0)

Hence, The potential is zero when the dipole is rotated through 90°.

#SPJ2