PracticeMedium
Q.A thin disc of radius b = 2a has a concentric hole of radius a in it (see figure). It carries uniform surface charge density σ. The electric field at the centre of the disc is (JEE Advanced 2017)
a
σ / (2 ε₀) (1 - 1/√2)
b
σ / (2 ε₀) (1 + 1/√2)
c
σ / (ε₀) (1 - 1/√2)
d
zero
Correct Answer: Option A
The correct solution involves applying the fundamental concept to derive the final value step by step...