In an LCR series circuit, the rms voltages across R, L and C are found to be 10 V, 10 V and 20 V respectively. The rms voltage across the entire combination is

Explanation

Impedance of the series circuit having capacitor and inductor,
`Z=X_C-X_L=(75-25)Omega=50Omega`
So, current `I=250/50=5A`
`therefore` Potential difference across the inductor,
`V_L=5times25V=125V`
and potential difference across the capacitor,
`V_C=5times75V=375V`
Now, main voltage,
V=250V
Hence, the relationship between `V,V_L` and `V_C` is `V=V_C-V_L`