A series R-C circuit is connected to an alternating voltage source. Consider two situations: (A) When capacitor is air filled (B) When capacitor is mica filled Current through resistor is i and voltage across capacitor […]
A resistance R draws power P when connected to an AC source. If an inductance is now placed in series with the resistance, such that the impedance of the circuit becomes Z the power drawn […]
A transformer having efficiency of 90% is working on 200 V and 3kW power supply. If the current in the secondary coil is 6 A, then the voltage across the secondary coil and the current […]
An alternating voltage e=200s in100t is applied to a series combination of R= 30Ω and an inductor of 400 mH. The power factor of the circuit is
Options
(a) 0.01 (b) 0.05 (c) […]
An ideal coil of 10 H is connected in series with a resistance of 5Ω and a battery fo 5 V. 2 second after the connection is made, the current flowing in ampere in the […]
In an AC circuit the potential differences across an inductance and resistance joined in series are respectively 16 V and 20 V. The total potential difference of the source is
Options
(a) 20.0 […]
An electric lamp is connected to 220 V, 50 Hz supply. Then the peak voltge is
Options
(a) 210 V (b) 211 V (c) 311 V (d) 320 V
Correct Answer:
311 V
In the series resonance the value of impedence is 3 Ω and the resistance is 4Ω, then the value of power factor of the circuit is
Options
(a) (4/3) (b) (3/4) (c) zero […]
An electric bulb has a rated power of 50W at 100 V. if it used on an a.c. source 200V, 50 Hz, a choke has to be used in series with it. This choke should […]
Two tangent galvanometers A and B have coils of radii 8 cm and 16 cm respectively and resistance 8 Ω each.They are connected in parallel with a cell of emf 4 V and negligible internal […]
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