When a charge of amount Q is given to an isolated metal plate X of surface area A, its surface charge density becomes `sigma_(1)`. When an isolated identical plate Y is brought close to X the surface charge density on X becomes `sigma_(2)`. When Y is earthed the surface charge density on X becomes `sigma_(3)`. Choose the incorrect option.

Options

A. `sigma_(1)=Q/A`
B. `sigma_(1)=Q/(2A)`
C. `sigma_(1)=sigma_(2)`
D. `sigma_(3)=Q/A`

Answer

B, C, D