PH 115 Lab 3: Resistors-Capacitors in AC/DC - Theory Questions

The plates of an isolated parallel plate capacitor with a capacitance C carry a charge Q. What is the capacitance of the capacitor if the charge is increased to 2Q?

a) None of these

b) C

c) 2C

d) C/2

b

Two capacitors in series that have the same charge density and same plate separation will always have the same

a) capacitance

b) none of these

c) voltage

d) charge

d

In an AC (sine wave) domain, the time series of the voltages between the capacitor and the resistor will ALWAYS be

a) exactly 180° out of phase

b) none of these

c) exactly in phase

d) exactly 90°

d

In an AC (sine wave) domain, the time series of the voltages between the capacitor and the entire circuit will ALWAYS be

a) exactly in phase

b) none of these

c) exactly 90°

d) exactly 180° out of phase

b

The capacitance will increase if we

a) increase the plate separation

b) increase the voltage

c) none of these

d) decrease the charge

c

One of the major differences between DC and AC (sine wave) when the circuit includes a capacitor is that

a) the capacitance depends on frequency

b) the capacitor has resistance, but independent of frequency

c) none of these

d) the capacitor has resistance, but dependent on frequency

d

In your DC experiment, when the capacitor was just beginning to charge, the current in the circuit was

a) between maximum and minimum

b) maximum

c) minimum

b

In your lab experiment, you considered a capacitor and resistor in series in AC (sine wave) domain. Did the time series of the voltage across the capacitor ever become zero?

a) yes

b) no

a

Capacitance depends on

a) charge

b) voltage

c) geometry and dielectric only

d) both voltage and charge

e) none of these

c

One of the major differences between DC and AC is that when the circuit includes a capacitor and a resistor in series,

a) no element in the circuit depends on frequency

b) the capacitance depends on frequency

c) the capacitance reactance depends on frequency

d) the resistance depends on frequency

c

In your lab experiment, you deduced that as the AC source frequency increases in an RC in series, the RMS voltage across the resistor

a) approaches zero

b) none of these

c) approaches the RMS of the source

c

In your lab experiment, you deduced that as the AC source frequency increases in an RC in parallel, then the RMS voltage across the entire circuit

a) goes to infinity

b) remains the same

c) approaches zero

b

In your lab experiment, you deduced that the speed of a capacitor discharging in a DC circuit depends on

a) the resistance only

b) the capacitance only

c) none of these

d) both on capacitance and resistance

d

In your lab experiment, you observed that the discharging capacitor would exhibit

a) the same polarity than it was charged at

b) the opposite polarity than it was charged at

b