Total electric force on an electric dipole placed in an electric field of a point charge is :

Options

A. always zero
B. never zero
C. zero when mid-point of dipole coincides with the point charge
D. zero when dipole axis is along any electric line of force.

Answer

To solve the question regarding the total electric force on an electric dipole placed in the electric field of a point charge, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Electric Dipole**: An electric dipole consists of two equal and opposite charges, +q and -q, separated by a distance 'd'. The dipole moment (p) is given by \( p = q \cdot d \).

2. **Electric Field of a Point Charge**: A point charge creates an electric field around it. The electric field (E) due to a point charge (Q) at a distance 'r' is given by:
\[ E = \frac{k \cdot |Q|}{r^2} \]
where \( k \) is Coulomb's constant.

3. **Force on Each Charge of the Dipole**: When the dipole is placed in the electric field of the point charge, each charge experiences a force due to the electric field. The force on the positive charge (+q) is:
\[ F_+ = q \cdot E \]
and the force on the negative charge (-q) is:
\[ F_- = -q \cdot E \]

4. **Net Force on the Dipole**: The total electric force (F_total) acting on the dipole is the vector sum of the forces acting on the positive and negative charges:
\[ F_{total} = F_+ + F_- = q \cdot E - q \cdot E = 0 \]
However, this is only true when the dipole is placed in a uniform electric field.

5. **Considering Non-Uniform Electric Field**: In the case of a point charge, the electric field is not uniform. The forces on the two charges of the dipole will not be equal because they are at different distances from the point charge. Therefore, the net force on the dipole will not be zero.

6. **Conclusion**: Since the electric field created by a point charge is non-uniform, the total electric force on the dipole placed in this field will never be zero. Thus, the correct answer is that the total electric force on an electric dipole placed in an electric field of a point charge is **never zero**.

### Final Answer:
The total electric force on an electric dipole placed in an electric field of a point charge is **never 0** (Option 2).