Advertisements
Advertisements
Question
Explain term impedance and state the formula for it in the case of an LCR series circuit.
Advertisements
Solution
(i) The ratio of rms voltage to the rms value of current is called impedance. The SI unit of impedance is the ohm (Ω).
(ii) The formula for impedance in case of an LCR series circuit,
Z = `sqrt("R"^2 + ("X"_"L" - "X"_"C")^2)`
Where, R= Resistance,
XL= Inductive reactance,
XC = Capacitive reactance.
APPEARS IN
RELATED QUESTIONS
Choose the correct option.
If the rms current in a 50 Hz AC circuit is 5A, the value of the current 1/300 seconds after its value becomes zero is ______.
In an AC circuit, e and i are given by e = 150 sin(150t)V and i = 150 sin `(150t + π/3)` A. The power dissipated in the circuit is ______.
An electric lamp is connected in series with a capacitor and an AC source is glowing with a certain brightness. How does the brightness of the lamp change on increasing the capacitance?
An electric current in an LC – circuit at resonance is called - ______
If AC voltage is applied to a pure capacitor, then the voltage across the capacitor ______
State the equation for impedance Z in an A.C. circuit.
If the peak value of an alternating emf is 15V, what is its mean value over half cycle?
A series LCR circuit has resistance 10Ω and reactance is `7sqrt2` Ω. What is the impedance of the circuit?
Find the current in a circuit consisting of a coil and a capacitor in series with an A.C source of 110V (r.m.s.), 60Hz. The inductance of a coil is 0.80 H and its resistance is 50Ω. The capacitance of a capacitor is 8µF.
What is the capacitive reactance of a capacitor of 5µF at a frequency of (1) 50 Hz and (2) 20KHZ?
Explain the term inductive reactance. State its unit and dimensions.
Obtain the expression for the applied emf and the effective resistance of the circuit when alternating emf is applied to an LR circuit.
Obtain the expression for the applied emf and the effective resistance of the circuit when alternating emf is applied to a CR circuit.
The standard voltage of A.C. mains in India is ______
In amplitude modulation. the amplitude of carrier wave is Ac and that of the modulating signal is Am· In practice, the ratio of Am to Ac is kept less than or equal to one, to avoid ______.
An RC Circuit as shown in the figure is driven by a AC source generating a square wave. The output wave pattern monitored by CRO would look close to:
A telegraph line of length 100 km has a capacity of 0.01 µF/ km and it carries an alternating current at 0.5 kilo cycle per second. If minimum impedance is required, then the value of the inductance that needs to be introduced in series is ______ mH. (if π = `sqrt10`)
