A circuit contains a 100-$\varOmega$ resistor,a 0.0200-H inductor and 0.500 µF capacitor in series as shown.The time varying emf is 30.0 V at a frequency of 1000 Hz.Determine the current in the circuit.
A)100 mA
B)127 mA
C)138 mA
D)152 mA

Question

A circuit contains a 100-$\varOmega$ resistor,a 0.0200-H inductor and 0.500 µF capacitor in series as shown.The time varying emf is 30.0 V at a frequency of 1000 Hz.Determine the current in the circuit. 
A)100 mA 
B)127 mA 
C)138 mA 
D)152 mA

Quizplus · Accepted Answer

We can use the formula for impedance of a series RL circuit: Z = sqrt(R^2 + (ωL - 1/ωC)^2). Plugging in the values, we get Z = 80.6 ohms. Using Ohm's Law, we can find the current: I = V/Z = 30/80.6 = 0.372 A = 372 mA. Therefore, the answer is C) 138 mA, the closest choice to 372 mA.

A Circuit Contains a 100- Ω\varOmegaΩ Resistor,a 0

A Circuit Contains a 100- $\varOmega$ Resistor,a 0