(Multiple choice)

(1) As the frequency in the simple ac circuit in Figure increases, the rms current through the resistor

(a) Increases.

(b) Does not change.

(c) May increase or decrease depending on the magnitude of the original frequency.

(d) May increase or decrease depending on the magnitude of the resistance.

(e) Decreases.

(2)
If the rms voltage in an ac circuit is doubled, the peak voltage is
(a) Increased by a factor of 2
(b) Decreased by a factor of 2
(c) Increased by a factor of √2
(d) Decreased by a factor of √2
(e) Not changed

(3)
If the frequency in the circuit shown in Figure is doubled, the inductance of the inductor will
(a) Increase by a factor of 2.
(b) Not change.
(c) Decrease by a factor of 2.
(d) Increase by a factor of 4.
(e) Decrease by a factor of 4.

(4)
If the frequency in the circuit shown in Figure is doubled, the inductive reactance of the inductor will
(a) Increase by a factor of 2.
(b) Not change.
(c) Decrease by a factor of 2.
(d) Increase by a factor of 4.
(e) Decrease by a factor of 4.

(5)
If the frequency in the circuit in Figure is doubled, the capacitative reactance of the circuit will
(a) Increase by a factor of 2.
(b) Not change.
(c) Decrease by a factor of 2.
(d) Increase by a factor of 4.
(e) Decrease by a factor of 4.

(6)

The SI units of inductance times capacitance are

(a) Seconds squared.

(b) Hertz.

(c) Volts.

(d) Amperes.

(e) Ohms.

(7) True or false:

(a) An RLC circuit with a high Q factor has a narrow resonance curve.

(b) At resonance, the impedance of an RLC circuit equals the resistance R.

(c) At resonance, the current and generator voltage are in phase.

(8)

A transformer is used to change

(a) Capacitance.

(b) Frequency.

(c) Voltage.

(d) Power.

(e) None of these.

(9)

True or false: If a transformer increases the current, it must decrease the voltage.

(10)

An ideal transformer has N₁ turns on its primary and N₂ turns on its secondary. The power dissipated in a load resistance R connected across the secondary is P₂ when the primary voltage is V₁. The current in the primary windings is then

(a) P₂/V₁.

(b) (N₁/N₂)(P₂/V₁).

(c) (N₂/N₁)(P₂/V₁).

(d) (N₂/N₁)²(P₂/V₁).

(11) True or false:

(a) Alternating current in a resistance dissipates no power because the current is negative as often as it is positive.

(b) At very high frequencies, a capacitor acts like a short circuit.

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