If both the resistance and the inductance in an LR AC series circuit are doubled the new impedance will be
Options
(a) halved (b) fourfold (c) doubled (d) quadrupled
Correct Answer:
doubled
Explanation:
For […]
The instantaneous values of alternating current and voltages in a circuit are given as i = 1/√2 sin (100πt) amper e = 1/√2 sin (100πt + π/3) Volt The average power in Watts consumed in […]
In R-L-C series circuit, the potential differences across each element is 20 V. Now the value of the resistance alone is doubled, then PD across R,L and C respectively.
Options
(a) 20 V, […]
The voltage of an a.c.supply varies with time (t) as V=120 sin 100 πt cos 100 πt the maximum voltage and frequency are respectively
Options
(a) 120 V and 100 Hz (b) 120√2 v […]
For a transformer, the turns ratio is 3 and its efficiency is 0.75. The current flowing in the primary coil is 2A and the voltage applied to it is 100 V. Then the voltage and […]
In an ac circuit an alternating voltage e = 200 √2 sin 100 t volts is connected to a capacitor of capacity 1 µF. The r.m.s. value of the current in the circuit is
If the alternating current I=I₁ cosωt+I₂ sinωt, then the rms current is given by
Options
(a) I₁+I₂/√2 (b) │I₁+I₂│/√2 (c) √(I₁²+I₂²/√2) (d) √I₁²+I₂²/√2
Correct Answer:
√(I₁²+I₂²/√2)
Explanation:
No explanation available. Be the first […]
An ac voltage is applied to a resistance R and an inductor L in series. If R and the inductive reactance are both equal to 3Ω, the phase difference between the applied voltage and the […]
Weber ampere per metre is equal to
Options
(a) Joule (b) Henry (c) Newton (d) Watt
Correct Answer:
Newton
Explanation:
weber = (emf) dt = (joule / charge) × time = joule / amp
The alternating current in a circuit is given by I=50 sin314t. The peak value and frequency of the current are
Options
(a) I₀=25 A and f=100 Hz (b) I₀=50 A and f=50 Hz (c) […]
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