The area of each plate of a parallel plate capacitor is 22 `cm^2` and the plates are kept separated by a paraffin paper of thickness 1mm. Specific inductive capacity of paraffin paper is 2. What are the capacitance of the capacitor and the surface density of charge under a potential difference of 330V?

Explanation

Capacitance of the capacitor,
`C= (k alpha)/( 4 pi d) [" Here ",k=2, alpha = 22 cm^2, d = 0.1 cm]`
`= (2xx22)/(4 pixx0.1) 35` statF
`:. Q = CV = 35 xx(330)/(300) statC[ :. V = 330V = (330)/(300) statV]`
Surface density of charge,
`sigma = (Q)/(alpha) = (35xx330)/(300xx22)= 1.75 statC * cm^(-2)`