Question

An LCR series circuit, connected to a source $E$, is at resonance. Then

• A. the voltage across R is zero
• B. the voltage across R equals applied voltage
• C. the voltage across C is zero
• D. the voltage across L equals applied voltage

Answer 1

Answer: (B)

the voltage across R equals applied voltage

Answer 2

Equation of voltage $E=\sqrt{V_{R}^{2}+\left(V_{L}-V_{C}\right)^{2}}$
At resonance (series fircuit)
$V_{L}=V_{C} \Rightarrow E=V_{R}$
ie, whole applied voltage appeared across the resistance.