If a current I given by flows in an ac circuit across which an ac potential of has been applied, then the power consumption P in the circuit will be
(1)
(2)
(3)
(4) P = 0
1. | \( 0.2~\text{sec}\) | 2. | \( 0.25~\text{sec}\) |
3. | \(25 \times10^{-3}~\text{sec}\) | 4. | \(2.5 \times10^{-3}~\text{sec}\) |
A resistance of \(300~\Omega\) and an inductance of \(\frac{1}{\pi}\) henry are connected in series to an AC voltage of \(20\) volts and a \(200\) Hz frequency. The phase angle between the voltage and current will be:
1. | \(\tan^{- 1} \dfrac{4}{3}\) | 2. | \(\tan^{- 1} \dfrac{3}{4}\) |
3. | \(\tan^{- 1} \dfrac{3}{2}\) | 4. | \(\tan^{- 1} \dfrac{2}{5}\) |
In a region of uniform magnetic induction B = 10–2 tesla, a circular coil of radius 30 cm and resistance π2 ohm is rotated about an axis that is perpendicular to the direction of B and which forms a diameter of the coil. If the coil rotates at 200 rpm the amplitude of the alternating current induced in the coil is :
(1) 4π2 mA
(2) 30 mA
(3) 6 mA
(4) 200 mA
In a LCR circuit having L = 8.0 henry, C = 0.5 μF and R = 100 ohm in series. The resonance frequency in radian per second is
(1) 600 radian/second
(2) 600 Hz
(3) 500 radian/second
(4) 500 Hz
The impedance of a circuit consists of 3 ohm resistance and 4 ohm reactance. The power factor of the circuit is :
(1) 0.4
(2) 0.6
(3) 0.8
(4) 1.0
The power factor of a good choke coil is:
(1) Nearly zero
(2) Exactly zero
(3) Nearly one
(4) Exactly one
1. | \(\frac{R}{4}\) |
2. | \(\frac{R}{2}\) |
3. | \(R\) |
4. | Cannot be found with the given data |