1. | \(\dfrac{E_{0}^{2}}{R} \sin^{2}\omega t\) | 2. | \(\dfrac{E_{0}^{2}}{R}\cos^{2}\omega t\) |
3. | \(\dfrac{E_{0}^{2}}{R}\) | 4. | \(\text{zero}\) |
In a step-up transformer, the turn ratio is \(1:20\). The resistance of \(100~\Omega\) connected across the secondary is drawing a current of \(2~\text{A}\).
What are the primary voltage and current respectively?
1. \(100~\text{V}, 0.5~\text{A}\)
2. \(200~\text{V},10~\text{A}\)
3. \(10~\text{V}, 40~\text{A}\)
4. \(10~\text{V}, 20~\text{A}\)
1. | The voltage leads the current by \(30^{\circ}\). |
2. | The current leads the voltage by \(30^{\circ}\). |
3. | The current leads the voltage by \(60^{\circ}\). |
4. | The voltage leads the current by \(60^{\circ}\). |
1. | \(10~\text{mA}\) | 2. | \(20~\text{mA}\) |
3. | \(40~\text{mA}\) | 4. | \(80~\text{mA}\) |
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. | \(V_R=V_C \neq V_L\) |
1. | \(20\) W | 2. | \(30\) W |
3. | \(10\) W | 4. | \(40\) W |
A capacitor of capacitance \(1~\mu\text{F}\) is charged to a potential of \(1\) V. It is connected in parallel to an inductor of inductance \(10^{-3}~\text{H}\).
What is the value of the maximum current that will flow in the circuit?
1. \(\sqrt{1000}~\text{mA}\)
2. \(1~\text{mA}\)
3. \(1~\mu\text{F}\)
4. \(1000~\text{mA}\)
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 |
1. | \(2500\) W | 2. | \(250\) W |
3. | \(5000\) W | 4. | \(4000\) W |