Advertisements
Advertisements
प्रश्न
When an alternating voltage of 220V is applied across device X, a current of 0.25A flows which lags behind the applied voltage in phase by π/2 radian. If the same voltage is applied across another device Y, the same current flows but now it is in phase with the applied voltage.
- Name the devices X and Y.
- Calculate the current flowing in the circuit when the same voltage is applied across the series combination of X and Y.
Advertisements
उत्तर
(i) In device X, the Current lags behind the voltage by π/2, X is an inductor.
In device Y, Current in phase with the applied voltage, and Y is resistor.
(ii) We are given that,
Current = `"V"/"X"_"L"`
Or, `0.25 = 220/"X"_"L"`,
∴ XL = 880Ω
Again, Current = `"V"/"R"`
Or, `0.25 = 220/"R"`
∴ R = 880Ω
For the series combination of X and Y,
Equivalent impedance Z = `sqrt(880^2 + 880^2)`
Z = `880sqrt2Omega`
Current = `"V"/"Z"`
Or, I = `220/(880sqrt2)`
∴ I = 0.177 A
APPEARS IN
संबंधित प्रश्न
Find the value of t/τ for which the current in an LR circuit builds up to (a) 90%, (b) 99% and (c) 99.9% of the steady-state value.
Use the expression for Lorentz force acting on the charge carriers of a conductor to obtain the expression for the induced emf across the conductor of length l moving with velocity v through a magnetic field B acting perpendicular to its length.
A series LCR circuit with R = 20 Ω, L = 1.5 H and C = 35 µF is connected to a variable-frequency 200 V ac supply. When the frequency of the supply equals the natural frequency of the circuit, what is the average power transferred to the circuit in one complete cycle?
In an L.C.R. series a.c. circuit, the current ______.
In series combination of R, L and C with an A.C. source at resonance, if R = 20 ohm, then impedence Z of the combination is ______.
Assertion: When the frequency of the AC source in an LCR circuit equals the resonant frequency, the reactance of the circuit is zero, and so there is no current through the inductor or the capacitor.
Reason: The net current in the inductor and capacitor is zero.
In an LCR circuit having L = 8 henery. C = 0.5 µF and R = 100 ohm in series, the resonance frequency in radian/sec is
Define Impedance.
Which of the following statements about a series LCR circuit connected to an ac source is correct?
Draw the impedance triangle for a series LCR AC circuit and write the expressions for the impedance and the phase difference between the emf and the current.
