An alternating current source of frequency 100 Hz is joined to a series combination of a resistance, a capacitance and a coil in series. The potential difference across the coil, the resistance and the capacitor is 46, 40 and 8 volt respectively. What is the electromotive force of alternating current source in volt ?

Options

A. 94
B. 14
C. 10
D. 76

Answer

C

Explanation

`V^2=V_R^2 + (V_L-V_C)^2`
`V_L=46, V_R=8, V_C=40`
`=8^2+(46-40)^2`
`=8^2+6^2`
=64+36
`V^2`= 100
`therefore` V=10 V