Five similar condenser plates, each of area A, are placed at equal distance d apart and are connected to a source of e.m.f. E as shown in the following diagram. The charge on the plates 1 and 4 will be

Options

A. `(epsi_(0)A)/(d), (-2epsi_(0)A)/(d)`
B. `(epsi_(0)AV)/(d), (-2epsi_(0)AV)/(d)`
C. `(-epsi_(0)AV)/(d),(-3epsi_(0)AV)/(d)`
D. `(epsi_(0)AV)/(d), (-4epsi_(0)AV)/(d)`

Explanation

From equivalent circuit diagram Charge on first plate Q=CV
`rArr Q=(epsi_(0)AV)/(d)`
Charge on fourth plate `Q'=C(-V)`
`Q=(-epsi_(0)AV)/(d)`
As plate 4 is repeated twice, hence charge on 4 will be Q''=2Q'
`Q''=-(2epsi_(0)AV)/(d)`
Hence the correct answer will be (B).