The r.m.s. voltage of the waveform shown is:
1. 10 V
2. 6.37 V
3. 7 V
4. 10.5 v
1. | \(10~\text{mA}\) | 2. | \(20~\text{mA}\) |
3. | \(40~\text{mA}\) | 4. | \(80~\text{mA}\) |
Voltage and current in an A.C. circuit is given by
Wattful current in the circuit is-
A time-varying current is given by Its r.m.s. value is (symbols have usual meanings)
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. | \(V_R=V_C \neq V_L\) |
For the circuit shown in figure below, the ammeter reads 1.6 A and ammeter read 0.4 A If is angular frequency and is frequency of ac, then
Given that the current \(i_1=3A \sin \omega t\) and the current \(i_2=4A \cos \omega t,\) what will be the expression for the current \(i_3\)?
1. \(5 A \sin \left(\omega t+53^{\circ}\right) \)
2. \(5 A \sin \left(\omega t+37^{\circ}\right) \)
3. \(5 A \sin \left(\omega t+45^{\circ}\right) \)
4. \( 5 A \sin \left(\omega t+30^{\circ}\right)\)
In a box \(Z\) of unknown elements (\(L\) or \(R\) or any other combination), an ac voltage \(E = E_0 \sin(\omega t + \phi)\) is applied and the current in the circuit is found to be \(I = I_0 \sin\left(\omega t + \phi +\frac{\pi}{4}\right)\). The unknown elements in the box could be:
1. | Only the capacitor |
2. | Inductor and resistor both |
3. | Either capacitor, resistor, and an inductor or only capacitor and resistor |
4. | Only the resistor |
The phase difference between emf and current through the choke coil maybe
1. 0
2. 85
3. 45
4. 30