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Alternating Current Circuits

Physics ⇒ Electricity and Magnetism

Alternating Current Circuits starts at 11 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Alternating Current Circuits. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.
See sample questions for grade 11
A 100 V, 60 Hz AC supply is connected to a 0.5\,\mu\text{F} capacitor. Calculate the capacitive reactance.
A 100\,\Omega resistor, a 0.2\,\text{H} inductor, and a 50\,\mu\text{F} capacitor are connected in series to a 230\,\text{V}, 50\,\text{Hz} AC supply. Calculate the impedance of the circuit.
A 200\,\Omega resistor is connected to a 100\,\text{V}, 50\,\text{Hz} AC supply. Calculate the rms current through the resistor.
A 50\,\text{Hz} AC voltage has a peak value of 325\,\text{V}. What is its rms value?
A 60\,\text{W}, 120\,\text{V} lamp is to be used on a 240\,\text{V}, 50\,\text{Hz} AC supply. What value of non-inductive resistance should be connected in series with the lamp?
A coil of inductance 0.5\,\text{H} and resistance 10\,\Omega is connected to a 100\,\text{V}, 50\,\text{Hz} AC supply. Calculate the impedance of the coil.
Calculate the rms value of an alternating current whose peak value is 10\,\text{A}.
Define the term 'impedance' in an AC circuit.
Describe the effect of increasing the resistance in a series RLC circuit on the sharpness of resonance.
Explain why alternating current is preferred over direct current for long-distance power transmission.
Explain why the power factor is important in AC circuits.
If the current in an AC circuit is given by I = 5 \sin(100\pi t), what is the frequency of the current?
If the frequency of the AC supply is doubled, what happens to the capacitive reactance?
If the rms value of an AC voltage is 220\,\text{V}, what is its peak value?
State one application of resonance in AC circuits.
State the condition for resonance in a series RLC circuit.
State the phase relationship between current and voltage in a purely inductive AC circuit.
What is the main function of a transformer in an AC circuit?
What is the unit of reactance?
A 60\,\text{W}, 120\,\text{V} lamp is to be operated on a 240\,\text{V}, 50\,\text{Hz} AC supply using a capacitor in series. What should be the value of the capacitor?