The figure shows a series LCR circuit connected to a variable frequency \(230~\text V\) source. \(L = 5.0~\text H, ~C = 80~\mu\text F, ~R = 40 ~\Omega.
\)
The RMS potential drop across the resistor under the resonating condition is:
1. \(200~\text V\)
2. \(220~\text V\)
3. \(230~\text V\)
4. Zero
A radio can tune over the frequency range of a portion of the MW broadcast band: (800 kHz to 1200 kHz). If its LC circuit has an effective inductance of 200 µH, what must be the range of its variable capacitor?
1. 87.8 pF−197.7 pF
2. 88.3 pF−198.8 pF
3. 89.3 pF−199.1 pF
4. 89.1 pF−196.9 pF
A series LCR circuit with R = 20 Ω, L = 1.5 H and C = 35 µF is connected to a variable-frequency 200 V ac supply. When the frequency of the supply equals the natural frequency of the circuit, what is the average power transferred to the circuit in one complete cycle?
1.2200 W
2.2000 W
3.2020 W
4. 2120 W
A 60 µF capacitor is connected to a 110 V, 60 Hz ac supply. The RMS value of the current in the circuit is:
1. 2.49 A
2. 2.12 A
3. 1.97 A
4. 1.24 A
A coil of inductance 0.50 H and resistance 100 is connected to a 240 V, 50 Hz ac supply. What is the maximum current in the coil?
1. 1.29 A
2. 1.82 A
3. 2.29 A
4. 2.82 A
A coil of inductance 0.50 H and resistance 100 Ω is connected to a 240 V, 50 Hz ac supply. What is the time lag between the voltage maximum and the current maximum?
1. 4.11×10−3 s
2. 2.10×10−3 s
3. 3.19×10−3 s
4. 2.23×10−3 s
A 100 µF capacitor in series with a 40 resistance is connected to a 110 V, 60 Hz supply. What is the maximum current in the circuit?
1. 2.19 A
2. 2.29 A
3. 3.14 A
4. 3.24 A
A circuit containing an 80 mH inductor and a 60 µF capacitor in series is connected to a 230 V, 50 Hz supply. The resistance of the circuit is negligible. What is the average power transferred to the inductor?
1. 18 J/s
2. 0
3. 12 J/s
4. 19 J/s
A series LCR circuit with L = 0.12 H, C = 480 nF, R = 23 is connected to a 230 V variable frequency supply. What is the source frequency for which current amplitude is maximum?
1. 444.4 Hz
2. 663.48 Hz
3. 545.0 Hz
4. 343.41 Hz