A series AC circuit has a resistance of \(4~\Omega\) and an inductor of reactance \(3~\Omega\). The impedance of the circuit is \(z_1\). Now when a capacitor of reactance \(6~\Omega\) is connected in series with the above combination, the impedance becomes \(z_2\). Then \(\frac{z_1}{z_2}\) will be:
1. \(1:1\)
2. \(5:4\)
3. \(4:5\)
4. \(2:1\)
A coil of inductive reactance of \(31~\Omega\) has a resistance of \(8~\Omega\). It is placed in series with a condenser of capacitive reactance \(25~\Omega\). The combination is connected to an AC source of \(110\) V. The power factor of the circuit is:
1. \(0.56\)
2. \(0.64\)
3. \(0.80\)
4. \(0.33\)
1. | \(60\) Hz and \(240\) V |
2. | \(19\) Hz and \(120\) V |
3. | \(19\) Hz and \(170\) V |
4. | \(754\) Hz and \(70\) V |
In an ac circuit, the current is given by \(i=5\sin(100t-\frac{\pi}{2})\) and the ac potential is \(V =200\sin(100 t)\) volt.
The power consumption is:
1. \(20\) W
2. \(40\) W
3. \(1000\) W
4. \(0\)
In an \(LCR\) circuit having \(L = 8.0~\text{H}\), \(C= 0.5~\mu\text{F}\) and \(R = 100~\Omega\) in series, what is the resonance frequency?
1. \(600\) radian/sec
2. \(600\) Hz
3. \(500\) radian/sec
4. \(500\) Hz
An AC source of variable frequency \(f\) is connected to an \(LCR\) series circuit. Which of the following graphs represents the variation of the current \(I\) in the circuit with frequency \(f\)?
1. | 2. | ||
3. | 4. |
1. | \(5000\) | 2. | \(50\) |
3. | \(500\) | 4. | \(5\) |