Question

Which of the following statements is not true about electric field lines?

• A. Electric field lines start from positive charge and end at negative charge.
• B. Two electric field lines can never cross each other.
• C. Electrostatic field lines do not form any closed loops.
• D. Electric field lines cannot be taken as continuous curve

Hint:

Remember: "Electric field lines are continuous, but they do NOT form closed loops." This is a key distinction that separates them from magnetic field lines, which always form closed loops!

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Electric field lines are a visual representation used to map out the electric field in space. They provide information about the direction of the field (via the tangent at any point) and its relative strength (via the density of the lines). These lines are governed by a set of rules that reflect the underlying physics of stationary charges and the conservative nature of the electrostatic force. Understanding what these lines can and cannot do is fundamental to visualizing electromagnetic theory.
Step 2: Key Formula or Approach:
We evaluate the physical validity of each option based on standard electrostatic properties:
1. Lines move from high potential (positive) to low potential (negative).
2. The field at any point must have a single unique vector direction.
3. Electrostatic work is path-independent, implying no closed loops.
4. Fields exist everywhere in space, so the lines representing them are continuous.
Step 3: Detailed Explanation:

Option (A) is a fundamental property: By convention, field lines are drawn starting from positive charges and terminating on negative charges. This is a true statement.

Option (B) is also a fundamental property: If two lines crossed at a point, it would mean the electric field at that point has two different directions simultaneously. This is physically impossible, so lines never cross. This is a true statement.

Option (C) reflects the conservative nature of the field: Electrostatic field lines are not like magnetic field lines; they do not loop back on themselves because the potential difference over a closed path must be zero. This is a true statement.

Option (D) states that field lines cannot be taken as continuous curves. This is false. Electric field lines are continuous curves that only break at the site of a charge. In a charge-free region, they are entirely continuous. Therefore, the statement in (D) is the one that is "not true."

Step 4: Final Answer:
The statement that is not true is: "Electric field lines cannot be taken as continuous curve".