Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Electrostatic Potential and Capacitance

Question:

The magnitude of electric field $\vec{E}$ in the annular region of a charged cylindrical capacitor :

Options:

is same throughout

is higher near the outer cylinder than near the inner cylinder

varies as $\frac{l}{r}$ where $r$ is the distance from the axis

varies as $\frac{l}{r^2}$ where $r$ is the distance from the axis

Correct Answer:

varies as $\frac{l}{r}$ where $r$ is the distance from the axis

Explanation:

The magnitude of electric field at a distance r from the axis is given as :

$E=\frac{\lambda}{2 \pi \varepsilon_0 r}$

i.e., $E \propto \frac{1}{r}$

Here, $\lambda$ is the charge per unit length of the capacitor.