Which of the following statements concerning the electrostatics is correct -

Options

A. electric line of force never intersect each other
B. electric lines of force start from positive charge and end at the negative charge
C. electric lines of force start or ends perpendicular to the surface lines of force start or ends perpendicular to the surface of a charged metal
D. all of the above

Answer

To determine which of the statements concerning electrostatics is correct, we will analyze each statement regarding electric lines of force.

### Step-by-Step Solution:

1. **Understanding Electric Lines of Force**:
- Electric lines of force are imaginary lines that represent the direction of the electric field. They help visualize how electric fields behave around charges.

2. **Analyzing Statement A**:
- **Statement**: Electric lines of force never intersect each other.
- **Explanation**: If two lines of force were to intersect, it would imply that at the point of intersection, there are two different directions of the electric field, which is not possible. Therefore, this statement is correct.

3. **Analyzing Statement B**:
- **Statement**: Electric lines of force start from positive charge and end at negative charge.
- **Explanation**: By convention, electric field lines originate from positive charges and terminate at negative charges. This is a fundamental property of electric fields. Therefore, this statement is also correct.

4. **Analyzing Statement C**:
- **Statement**: Electric lines of force start and end perpendicular to the surface of charged metal.
- **Explanation**: On a charged conductor, the electric field lines are indeed perpendicular to the surface. This is because the surface of a conductor is an equipotential surface, meaning the potential is constant across it. Therefore, this statement is correct.

5. **Conclusion**:
- All three statements (A, B, and C) are correct regarding electric lines of force. Therefore, the correct answer is that all of the above statements are true.

### Final Answer:
All of the above statements concerning electrostatics are correct.

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