Question

question 8 of 15
which of the following is a true statement?
a. electric field lines cross if they are between two like charges.
b. how closely packed the electric field lines are indicates the strength of the electric field.
c. it takes two charges to create an electric field.
d. electric field lines point toward positive charges.

Explanation:

• Option A: Electric field lines never cross. If they did, the electric field would have two directions at the crossing point, which is impossible. So this option is false.
• Option B: The density of electric field lines (how closely packed they are) indicates the strength of the electric field. More closely - packed lines mean a stronger electric field. This is a fundamental property of electric field lines.
• Option C: A single charge can create an electric field. For example, a point charge \(q\) creates an electric field \(\vec{E}=\frac{kq}{r^{2}}\hat{r}\) around it. So this option is false.
• Option D: Electric field lines point away from positive charges (since a positive test charge would be repelled) and towards negative charges. So this option is false.

Answer:

B. How closely packed the electric field lines are indicates the strength of the electric field.