In R-L-C series circuit, the potential difference across each element is 20 V. Now the value of hte resistance alone is doubled, then PD across R, L and C respectively.

Options

A. 20 V, 10 V , 10 V
B. 20 V, 20 V, 20 V.
C. 20V, 40 V, 40 V.
D. 10 V, 20 V, 20 V.

Answer

A

Explanation

(a) `X_(L) = X_(C) = R`
When resistance is doubled then impedance is also doubled .
`Z= sqrt((R-R)^(2)+(2R)^(2))=2R`
Current is halved .
Potential difference across resistance remains 20 V but it is halved for inductor and capacitor .
Hence option (a) is correct.