Exam 21: Alternating-Current Circuits

A circular coil of radius 10 cm and a separate square coil of side 20 cm are both rotated in a magnetic field of 1.5 T. If the circular coil is rotated at a frequency of 60 Hz, then at what frequency must the square coil be rotated in order for both coils to have the same maximum induced voltage?

A 5-μF capacitor is charged to 30 V and is then connected in series with a 10-μH inductor and a 50-Ω resistor. The potential difference across the inductor after a long time has passed will be

An AC motor can be turned into an AC generator by

You connect a 250-Ω resistor, a 1.20-mH inductor, and a 1.80-μF capacitor in series across a 60.0-Hz, 120-V peak) source. The resonant frequency of your circuit is approximately

As you increase the frequency in this circuit from zero, the impedance

You connect a 250-Ω resistor, a 1.20-mH inductor, and a 1.80-μF capacitor in series across a 60.0-Hz, 120-V peak) source. When you connect a voltmeter across the resistor in this circuit, the meter reads approximately

An AC power supply, V = V_o sin ωt, is connected in series to an inductor, capacitor, and resistor. The sum of the peak voltages across the inductor, capacitor, and resistor is

A series RLC circuit is driven by a 1.0-kHz oscillator. The circuit parameters are V_rms = 12 V, L = 5.0 mH, C = 4.0 μF, and R = 10 Ω. Under these conditions, the current

For a capacitor, the

You want the output current from the secondary coil of a transformer to be 10 times the input current to the primary coil. The ratio of the number of turns N₂/N₁ must be

A series RLC circuit with L = 5 H, C = 10 μF, and R = 10 Ω is driven by a generator with a maximum EMF of 100 V and a variable frequency. The resonant frequency f₀ of this circuit is

The diagram that correctly represents the phase relationship between the voltage across the resistor and the voltage across the capacitor in a circuit containing an inductor L, a capacitor C, and a resistor R all connected in series is

The figure shows the voltage and current for an)

The approximate resonant frequency of the circuit shown is

At what frequency would the reactance ) of a 10-μF capacitor be 100 Ω?

A motor sometimes burns out when its load is suddenly increased because the resulting sudden decrease in its rotational frequency causes

If you were to plug a 1200-W heater and a 600-W toaster into a 110-V electrical outlet, what total rms current would these two appliances draw if the wiring is parallel?

A flat, rectangular coil measuring 0.10 m by 0.20 m and containing 50 turns of wire is rotating at a constant speed of 100π rad/s in a magnetic field of 0.20 T. The maximum EMF induced in this coil is approximately

A 10-mH inductor has an internal resistance of 10 Ω. The impedance of this inductor for a frequency of 60 Hz is approximately

Two heaters are plugged into the same 120-V AC outlet. If one heater is rated at 1100 W, then what can be the maximum rating of the second heater in order not to exceed the 20 A trip rating on the circuit?