An RLC series circuit is connected to an oscillator with a maximum emf of 100 V.If the voltage amplitudes V_R, V_L, and V_C are all equal to each other, then V_R must be: A)33 V B)50 V C)67 V D)87 V E)100 V

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Quizplus · Accepted Answer

In an RLC series circuit at resonance, the voltages across the resistor (V_R), inductor (V_L), and capacitor (V_C) can be equal in magnitude but are not necessarily equal to the source voltage (V_S). However, when the question states that V_R, V_L, and V_C are all equal to each other and implies that this is under the condition of resonance without explicitly stating it, it suggests a specific scenario where the phasor sum of V_L and V_C equals zero due to their opposite phase angles, leaving only V_R in phase with the source voltage. Since V_R is directly influenced by the source voltage and the question suggests that all these voltages are equal and there's no phase difference between them and the source voltage, it implies that the entire source voltage appears across each component. Therefore, V_R must be equal to the maximum emf of the source, which is 100 V.

An RLC Series Circuit Is Connected to an Oscillator with a Maximum