Advertisements
Advertisements
Question
When an AC source is connected to a capacitor, there is a steady-state current in the circuit. Does it mean that the charges jump from one plate to the other to complete the circuit?
Advertisements
Solution
No. When an AC source is connected to a capacitor, there is a steady in the circuit to transfer change to the plates of the capacitor. This produces a potential difference between the plates. The capacitance is alternatively charged and discharged as the current reverses after each half cycle.
APPEARS IN
RELATED QUESTIONS
A current i1 = i0 sin ωt passes through a resistor of resistance R. How much thermal energy is produced in one time period? A current i2 = −i0 sin ωt passes through the resistor. How much thermal energy is produced in one time period? If i1 and i2 both pass through the resistor simultaneously, how much thermal energy is produced? Is the principle of superposition obeyed in this case?
Is energy produced when a transformer steps up the voltage?
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.
A capacitor acts as an infinite resistance for ______.
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 AC voltage across a resistance can be measured using
A bulb rated 60 W at 220 V is connected across a household supply of alternating voltage of 220 V. Calculate the maximum instantaneous current through the filament.
A transformer has 50 turns in the primary and 100 in the secondary. If the primary is connected to a 220 V DC supply, what will be the voltage across the secondary?
Average power supplied to a capacitor over one complete cycle is ______.
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.
A device ‘X’ is connected to an a.c source. The variation of voltage, current and power in one complete cycle is shown in figure.
- Which curve shows power consumption over a full cycle?
- What is the average power consumption over a cycle?
- Identify the device ‘X’.

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:
- the net reactance of the circuit
- the impedance of the circuit
- the effective value of current in the circuit.
A 40 µF capacitor is connected to a 200 V. 50 Hz ac supply. The rms value of the current on the circuit is, nearly ______.
In an alternating current circuit consisting of elements in series, the current increases on increasing the frequency of supply. Which of the following elements are likely to constitute the circuit?
When an AC voltage of 220 V is applied to the capacitor C ______.
A 10 µF capacitor is connected to a 210 V, 50 Hz source as shown in figure. The peak current in the circuit is nearly ______.
(π = 3.14)

