Question 1

An alternating current circuit has resistance R, inductance L and capacitance C in series with a voltage source.Which statement is correct?

Accepted Answer

A) The voltage across the capacitor leads the voltage across the inductor by 90 $\degree$. 
B) The voltage across the inductor leads the voltage across the capacitor by 90 $\degree$. 
C) The voltage across the inductor leads the voltage across the resistor by 180 $\degree$. 
D) The voltage across the inductor is out of phase with the voltage across the capacitor by 180 $\degree$. 
E) Both voltages lead the voltage across the resistor by 90 $\degree$. 
A) The voltage across the capacitor leads the voltage across the inductor by 90 $\degree$. 
B) The voltage across the inductor leads the voltage across the capacitor by 90 $\degree$. 
C) The voltage across the inductor leads the voltage across the resistor by 180 $\degree$. 
D) The voltage across the inductor is out of phase with the voltage across the capacitor by 180 $\degree$. 
E) Both voltages lead the voltage across the resistor by 90 $\degree$. D

Question 2

Capacitive reactance XC is given by:

Accepted Answer

A) 1/$ \omega $C 
B) ($ \omega $
C)  
C) ($ \omega $/
C)  
D) C/$ \omega $ 
E) 1/$ \omega $2C 
A) 1/$ \omega $C 
B) ($ \omega $
C)  
C) ($ \omega $/
C)  
D) C/$ \omega $ 
E) 1/$ \omega $2C A

Question 3

Suppose the circuit parameters in a series RLC circuit are: L = 1.00 $\mu$H, C = 10.0 nF, R = 100 $\Omega$, and the source voltage is 220 V.Determine the resonant frequency of the circuit and the amplitude of the current at resonance.

Accepted Answer

1.59 MHz, 2.20 A

Question 4

The graphs below show a voltage phasor at different instances of time.The voltage phasor which shows the instantaneous value of the voltage with the largest magnitude is:

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 5

The voltage 8.00 sin (400t) is applied to a series RLC circuit, with R = 200  $\Omega$, L = 0.100 H, and C = 1.00 $\mu$F.What are the impedance Z and the phase angle $\theta$ ?

Accepted Answer

A) 200  $\Omega$, -37.0 $\degree$ 
B) 566  $\Omega$, +87.0 $\degree$ 
C) 2 470  $\Omega$, -85.4 $\degree$ 
D) 2 540  $\Omega$, -88.8 $\degree$ 
E) 393  $\Omega$, -63.0 $\degree$ 
A) 200  $\Omega$, -37.0 $\degree$ 
B) 566  $\Omega$, +87.0 $\degree$ 
C) 2 470  $\Omega$, -85.4 $\degree$ 
D) 2 540  $\Omega$, -88.8 $\degree$ 
E) 393  $\Omega$, -63.0 $\degree$

Question 6

At what frequency will a 12-$\mu$F capacitor have a reactance XC = 300 $\Omega$ ?

Accepted Answer

A) 44 Hz 
B) 88 Hz 
C) 180 Hz 
D) 350 Hz 
E) 280 Hz 
A) 44 Hz 
B) 88 Hz 
C) 180 Hz 
D) 350 Hz 
E) 280 Hz

Question 7

An electric heater designed for export to the US market draws an average power of 1100 Watts when plugged into a typical US 110 V-rms outlet.Calculate the resistance of the heater and the rms current.

Accepted Answer

A) 11 $\Omega$ , 10 A (rms) 
B) 110 $\Omega$ , 10 A (rms) 
C) 10 $\Omega$ , 11 A (rms) 
D) 10 $\Omega$ , 110 A (rms) 
E) 0.09 $\Omega$ , 11 A (rms) 
A) 11 $\Omega$ , 10 A (rms) 
B) 110 $\Omega$ , 10 A (rms) 
C) 10 $\Omega$ , 11 A (rms) 
D) 10 $\Omega$ , 110 A (rms) 
E) 0.09 $\Omega$ , 11 A (rms)

Question 8

The total impedance Z of an RLC circuit driven by an ac voltage source at angular frequency $ \omega $ is:

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 9

If an R = 1.0-k $\Omega$ resistor, a C = 1.0-$\mu$F capacitor, and an L = 0.20-H inductor are connected in series with a V = 150 sin (377t) volts source, what is the maximum current delivered by the source?

Accepted Answer

A) 0.007 0 A 
B) 27 mA 
C) 54 mA 
D) 0.31 A 
E) 0.34 A 
A) 0.007 0 A 
B) 27 mA 
C) 54 mA 
D) 0.31 A 
E) 0.34 A

Question 10

In a parallel RLC circuit, where IR = IR, max sin($ \omega $t), the current through the inductor, IL, is:

Accepted Answer

A) IL = -IL, max sin($ \omega $t). 
B) IL = IL, max sin($ \omega $t). 
C) IL = -IL, max cos($ \omega $t). 
D) IL = IL, max cos($ \omega $t). 
E) IL = IL, max tan($ \omega $t). 
A) IL = -IL, max sin($ \omega $t). 
B) IL = IL, max sin($ \omega $t). 
C) IL = -IL, max cos($ \omega $t). 
D) IL = IL, max cos($ \omega $t). 
E) IL = IL, max tan($ \omega $t).

Question 11

An LC circuit is to have resonant oscillations at 5.0 MHz.Find the capacitance of a capacitor which will work with a 1.0-mH inductor.

Accepted Answer

A) 2.0 mF 
B) 1.0 $\mu$F 
C) 0.020 $\mu$F 
D) 1.0 pF 
E) 40 pF 
A) 2.0 mF 
B) 1.0 $\mu$F 
C) 0.020 $\mu$F 
D) 1.0 pF 
E) 40 pF

Question 12

The graphs below represent current and voltage phasors at one instant of time.The solid arrows represent the voltage phasors, $\Delta$V, and the dashed arrows represent the current phasors, Imax.The graph which shows the correct relationship between current and voltage phasors for an inductor in an RL circuit is:

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 13

What is the average power dissipation in an RLC series circuit with R = 10 $\Omega$, L = 0.1 H, C = 10 $\mu$F when driven at resonance by a 100 V-rms source?

Accepted Answer

A) 100 W 
B) 500 W 
C) 1000 W 
D) 2 kW 
E) 700 W 
A) 100 W 
B) 500 W 
C) 1000 W 
D) 2 kW 
E) 700 W

Question 14

Whenever the alternating current frequency in a series RLC circuit is halved:

Accepted Answer

A) the inductive reactance is doubled and the capacitive reactance is halved. 
B) the inductive reactance is doubled and the capacitive reactance is doubled. 
C) the inductive reactance is halved and the capacitive reactance is halved. 
D) the inductive reactance is halved and the capacitive reactance is doubled. 
E) the reactance of the circuit remains the same. 
A) the inductive reactance is doubled and the capacitive reactance is halved. 
B) the inductive reactance is doubled and the capacitive reactance is doubled. 
C) the inductive reactance is halved and the capacitive reactance is halved. 
D) the inductive reactance is halved and the capacitive reactance is doubled. 
E) the reactance of the circuit remains the same.

Question 15

Which of the following is true about a diode?

Accepted Answer

A) A diode causes the voltage to shift in phase by 90 $\degree$, i.e., a right angle. 
B) A diode has high resistance in one current direction and low resistance in the opposite current direction. 
C) A diode can only be used with a transformer. 
D) All filter circuits contain a diode. 
E) All of the above. 
A) A diode causes the voltage to shift in phase by 90 $\degree$, i.e., a right angle. 
B) A diode has high resistance in one current direction and low resistance in the opposite current direction. 
C) A diode can only be used with a transformer. 
D) All filter circuits contain a diode. 
E) All of the above.

Question 16

A step-up transformer has an input voltage of 110 V (rms).There are 100 turns on the primary and 1 500 on the secondary.What is the output voltage?

Accepted Answer

A) 1600 V (max) 
B) 1650 V (rms) 
C) 3260 V (max) 
D) 165 kV (rms) 
E) 7.3 V (rms) 
A) 1600 V (max) 
B) 1650 V (rms) 
C) 3260 V (max) 
D) 165 kV (rms) 
E) 7.3 V (rms)

Question 17

An ac generator with peak voltage 100 volts is placed across a 10- $\Omega$ resistor.What is the average power dissipated?

Accepted Answer

A) 100 W 
B) 150 W 
C) 500 W 
D) 1000 W 
E) 2000 W 
A) 100 W 
B) 150 W 
C) 500 W 
D) 1000 W 
E) 2000 W

Question 18

Calculate Vout/Vin for the circuit if R = 2.0 k $\Omega$, C = 0.020$\mu$F and V = 140V sin(50 000t).

Accepted Answer

A) 0.02 
B) 0.45 
C) 0.80 
D) 0.98 
E) 2.2 
A) 0.02 
B) 0.45 
C) 0.80 
D) 0.98 
E) 2.2

Question 19

Determine the impedance for the circuit.

Accepted Answer

A) 600  $\Omega$ 
B) 1200 $\Omega$ 
C) 1800  $\Omega$ 
D) 2300  $\Omega$ 
E) 1100  $\Omega$ 
A) 600  $\Omega$ 
B) 1200 $\Omega$ 
C) 1800  $\Omega$ 
D) 2300  $\Omega$ 
E) 1100  $\Omega$

Question 20

A 10.0-$\mu$F capacitor is plugged into a 110 V-rms 60.0-Hz voltage source, with an ammeter in series.What is the rms value of the current through the capacitor?

Accepted Answer

A) 0.202 A (rms) 
B) 0.415 A (rms) 
C) 0.626 A (rms) 
D) 0.838 A (rms) 
E) 0.066 A (rms) 
A) 0.202 A (rms) 
B) 0.415 A (rms) 
C) 0.626 A (rms) 
D) 0.838 A (rms) 
E) 0.066 A (rms)

Exam 11: Alternating-Current Circuits

An alternating current circuit has resistance R, inductance L and capacitance C in series with a voltage source.Which statement is correct?

Capacitive reactance XC is given by:

Suppose the circuit parameters in a series RLC circuit are: L = 1.00 μ\muμ H, C = 10.0 nF, R = 100 Ω\OmegaΩ , and the source voltage is 220 V.Determine the resonant frequency of the circuit and the amplitude of the current at resonance.

The graphs below show a voltage phasor at different instances of time.The voltage phasor which shows the instantaneous value of the voltage with the largest magnitude is:

The voltage 8.00 sin (400t) is applied to a series RLC circuit, with R = 200 Ω\OmegaΩ , L = 0.100 H, and C = 1.00 μ\muμ F.What are the impedance Z and the phase angle θ\thetaθ ?

At what frequency will a 12- μ\muμ F capacitor have a reactance XC = 300 Ω\OmegaΩ ?

An electric heater designed for export to the US market draws an average power of 1100 Watts when plugged into a typical US 110 V-rms outlet.Calculate the resistance of the heater and the rms current.

The total impedance Z of an RLC circuit driven by an ac voltage source at angular frequency ω \omega ω is:

If an R = 1.0-k Ω\OmegaΩ resistor, a C = 1.0- μ\muμ F capacitor, and an L = 0.20-H inductor are connected in series with a V = 150 sin (377t) volts source, what is the maximum current delivered by the source?

In a parallel RLC circuit, where IR = IR, max sin( ω \omega ω t), the current through the inductor, IL, is:

An LC circuit is to have resonant oscillations at 5.0 MHz.Find the capacitance of a capacitor which will work with a 1.0-mH inductor.

What is the average power dissipation in an RLC series circuit with R = 10 Ω\OmegaΩ , L = 0.1 H, C = 10 μ\muμ F when driven at resonance by a 100 V-rms source?

Whenever the alternating current frequency in a series RLC circuit is halved:

Which of the following is true about a diode?

A step-up transformer has an input voltage of 110 V (rms).There are 100 turns on the primary and 1 500 on the secondary.What is the output voltage?

An ac generator with peak voltage 100 volts is placed across a 10- Ω\OmegaΩ resistor.What is the average power dissipated?

Calculate Vout/Vin for the circuit if R = 2.0 k Ω\OmegaΩ , C = 0.020 μ\muμ F and V = 140V sin(50 000t).

Determine the impedance for the circuit.

A 10.0- μ\muμ F capacitor is plugged into a 110 V-rms 60.0-Hz voltage source, with an ammeter in series.What is the rms value of the current through the capacitor?

Electric Fields

Gausss Law

Electric Potential

Energy and Capacitance

Current and Resistance

Direct-Current Circuits

Magnetic Fields

Magnetic Forces

Faradays Law

Inductance

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarisation

Quantisation and Wave-Particle Duality

Introduction to Quantum Mechanics

Atomic Physics

Quantum Physics of Molecules and Solids

Nuclei and Radioactivity

Particle Physics

Filters

Suppose the circuit parameters in a series RLC circuit are: L = 1.00 $\mu$ H, C = 10.0 nF, R = 100 $\Omega$ , and the source voltage is 220 V.Determine the resonant frequency of the circuit and the amplitude of the current at resonance.

The voltage 8.00 sin (400t) is applied to a series RLC circuit, with R = 200 $\Omega$ , L = 0.100 H, and C = 1.00 $\mu$ F.What are the impedance Z and the phase angle $\theta$ ?

At what frequency will a 12- $\mu$ F capacitor have a reactance XC = 300 $\Omega$ ?

The total impedance Z of an RLC circuit driven by an ac voltage source at angular frequency $\omega$ is:

If an R = 1.0-k $\Omega$ resistor, a C = 1.0- $\mu$ F capacitor, and an L = 0.20-H inductor are connected in series with a V = 150 sin (377t) volts source, what is the maximum current delivered by the source?

In a parallel RLC circuit, where IR = IR, max sin( $\omega$ t), the current through the inductor, IL, is:

What is the average power dissipation in an RLC series circuit with R = 10 $\Omega$ , L = 0.1 H, C = 10 $\mu$ F when driven at resonance by a 100 V-rms source?

An ac generator with peak voltage 100 volts is placed across a 10- $\Omega$ resistor.What is the average power dissipated?

Calculate Vout/Vin for the circuit if R = 2.0 k $\Omega$ , C = 0.020 $\mu$ F and V = 140V sin(50 000t). $Calculate Vout/Vin for the circuit if R = 2.0 k \Omega , C = 0.020 \mu F and V = 140V sin(50 000t).$

A 10.0- $\mu$ F capacitor is plugged into a 110 V-rms 60.0-Hz voltage source, with an ammeter in series.What is the rms value of the current through the capacitor?