# physics, help with circuits please!

posted by
**Jim** on
.

Can the voltage across any of the three components in the R-L-C series circuit ever be larger than the maximum voltage supplied by the AC source? That maximum voltage is 50 volts in this situation. Also, does Kirchoff's loop rule apply to this circuit? In other words, is the sum of the voltages across the resistor, capacitor, and inductor always equal to the source voltage? Select all the true statements from the list below.

1. The voltage across the resistor can exceed the maximum source voltage.

2.

The voltage across the inductor can exceed the maximum source voltage.

3.

The voltage across the capacitor can exceed the maximum source voltage.

4.

None of these voltages can ever exceed the maximum source voltage.

5.

Kirchoff's loop rule is only valid for DC circuits, and does not apply to this AC situation.

6.

Kirchoff's loop rule can be applied to AC circuits, but not to this circuit in particular.

7.

Kirchoff's loop rule is valid for this circuit - at all times the sum of the voltages across the resistor, capacitor, and inductor equal the source voltage.

(b) Resonance is a very special condition in an AC circuit. The resonance frequency is the natural oscillation frequency of the circuit itself, so when the source frequency equals the resonance frequency some special things happen. Select all the statements below that are true at resonance.

8.

For a particular set of R, L, and C values, the current in the circuit is maximized when the circuit is at its resonance frequency.

9.

For a particular set of R, L, and C values, the current in the circuit is minimized when the circuit is at its resonance frequency.

10.

For a particular set of R, L, and C values, the impedance Z of the circuit is maximized when the circuit is at its resonance frequency.

11.

For a particular set of R, L, and C values, the impedance Z of the circuit is minimized when the circuit is at its resonance frequency.

12.

For a particular set of R, L, and C values, the magnitude of the phase angle is zero when the circuit is at its resonance frequency.

13.

For a particular set of R, L, and C values, the magnitude of the phase angle is 90 degrees when the circuit is at its resonance frequency.

14.

For a particular set of R, L, and C values, the power dissipated in the circuit is maximized when the circuit is at its resonance frequency.

15.

For a particular set of R, L, and C values, the power dissipated in the circuit is minimized when the circuit is at its resonance frequency.