Question

Consider two infinitely large plane parallel conducting plates as shown below. The plates are uniformly charged with a surface charge density \(+ \sigma\)  and \(-2 \sigma\). The force experienced by a point charge \(+q\) placed at the mid point between two plates will be :

(1) \(\frac{\sigma q}{4 \ \in_0}\)

(2) \(\frac{3 \sigma q}{2 \ \in _0}\)

(3) \(\frac{3 \sigma q}{4 \ \in _0}\)

(4) \(\frac{\sigma q}{2 \ \in _0}\)

Answer 1

Correct option is : (2) \(\frac{3 \sigma q}{2 \in _0}\)

Final charge distribution will be

\(\therefore \ F_{\text{net}} = \frac{3\sigma}{2 \ \in _0}q\)