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प्रश्न
A capacitor acts as an infinite resistance for ______.
विकल्प
DC
AC
DC as well as AC
neither AC nor DC
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उत्तर
A capacitor acts as an infinite resistance for DC.
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संबंधित प्रश्न
Show that the current leads the voltage in phase by π/2 in an AC circuit containing an ideal capacitor ?
A transformer is designed to convert an AC voltage of 220 V to an AC voltage of 12 V. If the input terminals are connected to a DC voltage of 220 V, the transformer usually burns. Explain.
An AC source producing emf ε = ε0 [cos (100 π s−1)t + cos (500 π s−1)t] is connected in series with a capacitor and a resistor. The steady-state current in the circuit is found to be i = i1 cos [(100 π s−1)t + φ1) + i2 cos [(500π s−1)t + ϕ2]. So,
The peak voltage of a 220 V AC source is
Compare resistance and reactance.
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- How does the reactance of the device Y vary with the frequency of the AC? Show graphically.
- Draw the phasor diagram for device Y.
Suppose the initial charge on the capacitor is 6 mC. What is the total energy stored in the circuit initially? What is the total energy at later time?
Average power supplied to a capacitor over one complete cycle is ______.
When an ac voltage of 220 V is applied to the capacitor C, then ______.
An alternating current of 1.5 mA and angular frequency 300 rad/sec flows through a 10 k Ω resistor and a 0.50 µF capacitor in series. Find the rms voltage across the capacitor and impedance of the circuit.
When an AC voltage of 220 V is applied to the capacitor C ______.
- the maximum voltage between plates is 220 V.
- the current is in phase with the applied voltage.
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A resistor of 50 Ω, a capacitor of `(25/pi)` µF and an inductor of `(4/pi)` H are connected in series across an ac source whose voltage (in volts) is given by V = 70 sin (100 πt). Calculate:
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- the impedance of the circuit
- the effective value of current in the circuit.
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