Voltage and current in an ac circuit are given by \(V=5sin\left ( 100\pi t-\frac{\pi }{6}~ \right )~V\) and \(I=4sin\left ( 100\pi t+\frac{\pi }{6}~ \right )~A.\)
Hence:
1. | The voltage leads the current by 30°. |
2. | The current leads the voltage by 30°. |
3. | The current leads the voltage by 60°. |
4. | The voltage leads the current by 60°. |
The r.m.s. voltage of the waveform shown is:
1. 10 V
2. 6.37 V
3. 7 V
4. 10.5 v
If potential differences measured in ac voltmeters across the inductor, capacitor, and resistor in series LCR ac circuit are 100 V, 100 V, and 50 v respectively, then the peak value of the applied ac voltage to the circuit is
1. 50 V
Voltage and current in an A.C. circuit is given by
Wattful current in the circuit is-
Which of the following devices is not based on Faraday's law of electromagnetic induction?
1. AC generator
2. Speedometer
3. Induction motor
4. DC motor
Current l through an inductor is increasing according to . Variation of the rate of increment of its energy with time t is correctly shown in the graph
1. 2.
3. 4.
A time-varying current is given by Its r.m.s. value is (symbols have usual meanings)
An alternating voltage at different frequencies is applied across a capacitor C as shown in the figure. Which of the following graphs between RMS current observed by an ammeter and angular frequency of voltage is correct?
1. 2.
3. 4.
It is found that the current through the LCR series circuit is at its maximum. If are potential differences across resistance, capacitor, and inductor respectively, then which of the following is correct?
1. | \(V_r=V_L>V_C\) |
2. | \(V_R \neq V_L=V_C\) |
3. | \(V_R \neq V_L \neq V_C\) |
4. | \(V_R=V_C \neq V_L\) |
In a series L-C-R circuit, different physical quantities vary with frequency . Which of the following curves represent the correct frequency variation of the corresponding quantity?
1. Curve (l) for R
2. Curve (ll) for
3. Curve (lll) for
4. All of these