Advertisements
Advertisements
प्रश्न
In a circuit, containing a capacitor and an AC source, the current is zero at the instant the source voltage is maximum. Is it consistent with Ohm's Law?
उत्तर
Ohm's Law is valid for resistive circuits only. It is not valid for capacitive or inductive circuits, or a combination of both.
APPEARS IN
संबंधित प्रश्न
When an AC source is connected to an ideal inductor show that the average power supplied by the source over a complete cycle is zero.
Ajit had a high tension tower erected on his farm land. He kept complaining to the authorities to remove it as it was occupying a large portion of his land. His uncle, who was a teacher, explained to him the need for erecting these towers for efficient transmission of power. As Ajit realised its significance, he stopped complaining.
Answer the following questions:
(a) Why is it necessary to transport power at high voltage?
(b) A low power factor implies large power loss. Explain.
(c) Write two values each displayed by Ajit and his uncle.
A lamp is connected in series with an inductor and an AC source. What happens to the brightness of the lamp when the key is plugged in and an iron rod is inserted inside the inductor? Explain.
An A.C. generator generating an emf of ε = 300 sin (100 πt) V is connected to a series combination of 16μ F capacitor, 1 H inductor and 100 Ω resistor.
Calculate :
1) An impedance of the circuit at the given frequency.
2) Resonant frequency `f_0`
3)Power factor at the resonant frequency `f_0`.
Can you have an AC series circuit in which there is a phase difference of (a) 180° (b) 120° between the emf and the current?
A resistance is connected to an AC source. If a capacitor is included in the series circuit, will the average power absorbed by the resistance increase or decrease? If an inductor of small inductance is also included in the series circuit, will the average power absorbed increase or decrease further?
In an AC series circuit, the instantaneous currt is zero when the instantaneous voltage is maximum. Connected to the source may be a
(a) pure inductor
(b) pure capacitor
(c) pure resistor
(d) combination of an inductor and a capacitor
The current in a discharging LR circuit is given by i = i0 e−t/τ , where τ is the time constant of the circuit. Calculate the rms current for the period t = 0 to t = τ.
Following figure shows a typical circuit for a low-pass filter. An AC input Vi = 10 mV is applied at the left end and the output V0 is received at the right end. Find the output voltage for ν = 10 k Hz, 1.0 MHz and 10.0 MHz. Note that as the frequency is increased the output decreases and, hence, the name low-pass filter.
What is the value of power factor for a pure resistor connected to an alternating current source ?
An ac circuit as shown in the figure has an inductor of inductance L and a resistor of resistance R connected in series. Using the phasor diagram, explain why the voltage in the circuit will lead the current in phase.
In previous questions 3 and 4, what is the net power absorbed by each circuit over a complete cycle. Explain your answer.
Quality factor and power factor both have the dimensions of ______.
The power factor of an a.c circuit having resistance R and inductance L Connected in series to an a.c source of angular frequency co is.
In an AC. circuit, the current is :
i = `5 sin (100t - pi/2)` amp.
and the a.c. potentiol is:
V = 200 sin (100t) volt.
Then the power consumption is
A 100 Ω electric iron is connected to 200 V, 50 Hz ac source. Calculate average power delivered to iron, peak power and energy spent in one minute?
The coefficient of induction of a choke coil is 0.1 H and resistance is 12 Ω. If it is connected to an a.c source of frequency 60Hz. Then the power factor will be ______.
An alternating current I = 14 sin (100 πt) A passes through a series combination of a resistor of 30 Ω and an inductor of `(2/(5pi))` H. Taking `sqrt2` = 1.4 calculate the power factor of the circuit.
