Question

What is the number of electric field lines coming out from a 1C charge?

• A. $9 \times 10^9$
• B. $8.85 \times 10^{-12}$
• C. $\frac{1}{8.85} \times 10^{-12}$
• D. Infinite

Answer 1

Answer: (D)

Infinite

Answer 2

The number of electric field lines is a conceptual tool to represent the magnitude of the electric field; field lines are not physically countable. Although Gauss's law gives the electric flux as

$$\Phi = \frac{Q}{\epsilon_0},$$

this flux is represented using an arbitrarily chosen number of field lines. Hence, there is no unique number of field lines that “come out” from a 1 C charge.

Explanation (minimal):

Field lines are a pictorial representation that shows the relative strength of the electric field. Their number is arbitrarily chosen; thus, for any given charge including 1 C, the number of lines is not quantifiable—it is considered infinite.