2021 Electric Charges and FieldsElectric Dipole in a Non-uniform Electric Field Hard Question 11 of 42 in Electric Charges and Fields

A dipole is placed in an electric field as shown. In which direction will it move?

A towards the right as its potential energy will decrease.
B towards the left as its potential energy will decrease.
C towards the right as its potential energy will increase.
D towards the left as its potential energy will increase.

The answer is A.

Solution


The field lines are closer at the charge +q, so $|E_1| > |E_2|$.
The force on +q (towards the right) is greater than the force on –q (towards the left), so the net force on the dipole acts towards the right.
A system always moves so as to decrease its potential energy. So the dipole moves towards the right as its potential energy decreases.

Concept motion of a dipole in a non-uniform field

Electric Charges and Fields in past papers

42 questions from this chapter have appeared across 23 exam years.