Electric field and enclosed charge – Rankers Physics

Electric Flux: Practice Problem & Solution

The electric field in a region is directed outward and is proportional to the distance \(r\) from the origin. If we take a spherical volume of radius \(r\) taking centre at the origin, then the charge contained inside the volume is proportional to
\(r\)
\(r^2\)
\(r^0\)
\(r^3\)

Solution Explained:

To solve this problem, we apply the core principles of Electric Flux. Understanding the underlying formula is key to arriving at the correct answer below:

From Gauss's Law, the enclosed charge is proportional to the electric flux: \(q \propto E \cdot A\). Since \(E \propto r\) and area \(A \propto r^2\), we get \(q \propto r \cdot r^2 = r^3\).

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