A conducting sphere A of radius a, with charge Q is placed concentrically inside a conducting shell B of radius b. B is earthed, C is the common centre of A and B. If P is the point between shells A and B at distance r from center C then Match the proper entries from column-2 to column-1 using the codes given below the columns,
(use `a=1m,b=3m,r=2m` and `K=(1)/(4piepsilon_(o))`)

Options

A. `{:(P,Q,R,S),(3,1,2,4):}`
B. `{:(P,Q,R,S),(1,2,3,4):}`
C. `{:(P,Q,R,S),(2,3,4,1):}`
D. `{:(P,Q,R,S),(3,4,1,2):}`

Explanation

Field at P is only due to `A=(kQ)/((2)^(2))=(kQ)/(4)`
Potential at `P=V_("due to A")+V_("due to B")=(kQ)/(2)-(kQ)/(3)`
electric field outside B is due to A s lnduced charge on B+a's charge = zero.