Class 2

Class 2Today we will:• learn the basic characteristics of the electrostatic force• review the properties of conductors and insulators• learn what is meant by “electrostatic induction”• find out why static electrostatic forces are usually attractive• discuss the problem of force at a distance• learn the basics of two types of models that explain why there are forces

Clicker Question 1

When babies are rubbed, they gain a net charge.Does the ceiling need a net charge for the babiesto stick to it?

A. yesB. no

Clicker Question 2

If the ceiling has no net charge, is it possible for thebabies to be repelled by the ceiling?

A. yesB. no

Clicker Question 3

If the virtual particles were uncharged real particles, the force would be

A. always attractive.B. always repulsive.C. either attractive or repulsive.D. There would be no force.

Answers

1B2B3B

Class 3Today we will:• learn how the thread model describes the force between point charges at rest• construct Coulomb’s law from the thread model• learn how to use Coulomb’s law to calculate the force between charges at rest

Clicker Question 1

The field particle isA. positiveB. negativeC. neutralD. You can’t tell.

source charge field charge

Force

+3C

(2, 3)

−4C

(7, 1)

304 r

rqqF fs

Clicker Question 2

If we wish to find the force on the blue particle,A. the blue particle is the source particle.B. the blue particle is the field particle.C. both particles are source particles.D. both particles are field particles.E. none of the above.

+3C

(2, 3)

−4C

(7, 1)

304 r

rqqF fs

Clicker Question 3

The vector goes from the source particle tothe field particle.

r

39.5 E.

ˆ2ˆ5 D.

ˆ2ˆ5 C.

ˆ3ˆ2 B.

ˆ1ˆ7 A.

r

yxr

yxr

yxr

yxr

Answers

1A2B3D

Class 4Today we will:• review the meaning of potential energy• find the potential energy of point charges at rest• learn a few basic ideas about relativity• find out how relativity affects the threads emitted by a moving source

Clicker Question 1

In a region of space, the force on a positive testcharge is zero. In this region, the potential energy is

A. positive.B. negative.C. zero.D. a constant, but not necessarily zero.

0F

Clicker Question 2

c

v

The SI units for β are:A. m/s2

B. m2/sC. m2/s2

D. β is dimensionless

rest moving

H'

L'

H

L

0

Clicker Question 3

0

0

0

0

0

and .E

and .D

and .C

and .B

and .A

LL

HH

LL

HH

LL

Answers

1D2D3E

Class 5Today we will:• learn the meaning of head lines, tail lines, and ray lines.• find a force equation for a moving source charge (like Coulomb’s law, but for a source with constant velocity).• learn how stubs can be used to make a account for the motion of field particles.

Clicker Question 1

U

P

S

A source charge and a field charge are both positive. The source at S emits threads that arrive at P when the source has moved to U.

What is the direction of the thread?

A

B

C

D

E - out of screen

Clicker Question 2

U

P

S


What is the direction of the thread (electric) force?

A

B

C

D

E - out of screen

Clicker Question 3

U

P

S


What is the direction of the head line?

A

B

C

D

E - out of screen

Clicker Question 4

U

P

S


What is the direction of the stub?

A

B

C

D

E - out of screen

Clicker Question 5

U

P

S


What is the direction of the stub (magnetic) force?

A

B

C

D

E - out of screenv

Answers

1B2B3D4E5D

Class 6Today we will:• learn that threads and stubs can be aligned to form electric and magnetic field lines.• derive the Lorentz force law.• integrate to find the electric and magnetic fields of a proton beam.

Clicker Question 1

U

P

S


What is the direction of the stubs?

A

B

C

D

E - out of screen

Clicker Question 2

A proton travels vertically downward through aregion where there is an electric field pointingto the east.

What is the direction of the force?

A. downwardB. to the eastC. to the southD. to the northE. to the west

Clicker Question 3

A proton travels vertically downward through aregion where there is a magnetic field pointingto the east.



Clicker Question 4

An electron travels vertically downward through aregion where there is a magnetic field pointingto the east.



Answers

1E2B3C4D

Class 7Today we will:• learn how to do problems using the Lorentz force law.• learn the meaning of the electric potential and how it relates to the potential energy.• learn three ways of representing fields geometrically.

Clicker Question 1

.ˆ mT 00.2ˆ mT 50.3 yxB .ˆ m/s 00.5 xv

If we change the magnetic field to

what happens to the force?

A. It doubles.B. Its get smaller by a factor of 2.C. Its z-component doubles.D. Its z-component gets smaller by factor of 2.E. Nothing changes.

.ˆ mT 00.2ˆ mT 00.7 yxB

Before:

Clicker Question 2

An electron passes through a 1.0 V battery. Theelectron charge is

By how much does the energy of the electron increase?

J.0U D.

J.10801.0U C.

J.10204.3U B.

J.10602.1U A.

19

19

19

C.10602.1 19e

Clicker Question 2

An electron passes through a 1.0 V battery. Theelectron charge is

Batteries increase the potential energy of electrons by pushing them closer together.

C.10602.1 19e

Clicker Question 3

Two identical spheres have charges +q. Theyare separated by a distance d.

At the midpoint between the spheres, the magnitude of the electric field is:

0E E.

4

1E D.

2

4

1E C.

4

4

1E B.

8

4

1E A.

20

20

20

20

d

q

d

q

d

q

d

q

+q +q

Clicker Question 4

Two identical spheres have charges +q. Theyare separated by a distance d.

At the midpoint between the spheres, the electric potential is:

0V E.

24

1V D.

4

1V C.

2

4

1V B.

4

4

1V A.

00

00

d

q

d

q

d

q

d

q

+q +q

Answers

1E2A3E4A

Class 8Today we will:• learn about static electric fields and electric potentials in conductors.• learn how charges move in regions where there are electric and magnetic fields.• learn about some practical devices that use electric and magnetic fields.

Clicker Question 1

A net charge of +1.0 mC is placed on a steel ball.The ball is then placed in the electric field of aVan de Graaff generator. The total charge on the surface of the steel ball is:

A. zeroB. + 0.5 mCC. – 0.5 mCD. + 1.0 mCE. – 1.0 mC

Clicker Question 2

After a positive charge is “shot” into a region where there is a uniform magnetic field, it spirals clockwiseout of the screen. If a negative charge were shot into this region, it would:

A. spiral clockwise out of the screenB. spiral clockwise into the screenC. spiral counterclockwise out of the screenD. spiral counterclockwise into the screen

Answers

1D2C

Class 9Today we will:• learn about current, voltage, and power in circuits.• learn about resistance of materials and how resistance depends on geometry and temperature.• introduce Ohm’s law.

Clicker Question 1

What current passes through a 60 W light bulb?(Line voltage is 120 V.)

A. 0.5 AB. 1.0 AC. 2.0 AD. 7200 AE. All of the above

Clicker Question 2

One block has resistance R. What is the resistance when two blocks are joined at the midpoints as shown:

A.R/2B.RC.3R/2D.5R/4E.2R

Clicker Question 2

One block has resistance R. What is the resistance when two blocks are joined at the midpoints as shown:

A.R/2B.RC.3R/2D.5R/4E.2R

Hint: Divide the combination into three regions.

Answers

1A2D

Class 10Today we will:• learn how to determine if two resistors are in series or parallel.• find out how resistors combine when connected in series and parallel.• work examples of series-parallel reduction to find current, voltage and power in resistance networks.

Clicker Questions 1-6Series-Parallel Quiz

Answer the following six questions to see if you understand what

series and parallel mean.

1. Resistors A and B are in

1. series

2. parallel

3. neither


1. series

2. parallel

3. neither


1. series

2. parallel

3. neither


1. series

2. parallel

3. neither


1. series

2. parallel

3. neither


1. series

2. parallel

3. neither

Quiz Answers1. series2. neither3. neither4. parallel5. series 6. parallel

Class 11Today we will:• discuss Kirchoff’s loop and node equations.• learn how to determine the number of loop and the number of node equations we will need.• write Kirchoff’s equations for a sample circuit.

I2

I1

I3

I4 I5

I6

A

B

C

D

Clicker Question 1

The junction equation for junction A is:

0 E.

D.

C.

B.

A.

361

613

163

613

321

III

III

III

III

III

I2

I1

I3

I4 I5

I6

A

B

C

D

12

3

+

+

+

+

+

+

+

+

Clicker Question 2

The loop equation for loop 2 is:

076623 E.

076623 D.

076623 C.

076623 B.

06 A.

65556

6536

6536

6536

6536

IIIII

IIII

IIII

IIII

IIII

Answers

1C2D

Class 12Today we will:• discuss test policies.• review Lessons 1 – 4 to prepare for the exam.

Clicker Question 1

Your answer is 0.00467. What is the first significant digit?

A: 0B: 4C: 5

Clicker Question 2

Your answer is 1.38×103. What is the exponent?

A: 1B: 2C: 3D: 4

Answers

1B2C

Class 13Today, we will:• review characteristics of field lines and contours• learn more about electric field lines and contours of point charges• learn more about magnetic fields and contours of long, straight wires

Clicker Question 1

The strength of a field is given in terms of field lines by:

A.the number of lines per unit length.B.the number of contours per unit

length.C.the number of lines per unit area.D.the number of contours per unit area.

Clicker Question 2

The wire law for magnetic fields is represented geometrically by

A.the magnetic field lines.B.the magnetic field contours.C.the electric field lines.D.the electric field contours.

Answers

1C2B

Class 14Today, we will:• learn how to draw the total electric field of two point charges.• find that the electric field is like a single point in the near field and the far field.• use symmetry to find the electric field lines of charged spheres, cylinders, and planes.

Clicker Question 1Is this picture OK?A – yes B -- no

+1 –1

Clicker Question 1Is this picture OK?A – yes B -- no

+1 –1

•Field lines can not cross.•The near field is incorrect.

Clicker Question 2Is this picture OK?A – yes B -- no +2 –1

Clicker Question 2Is this picture OK?A – yes B -- no +2 –1

•The far field is incorrect.•The near field isn’t drawn well.

Answers

1B2B

Class 15Today, we will:• learn to visualize magnetic field lines for two wires.• learn to visualize electric and magnetic field contours for two charges or wires.

Clicker Question 1In three dimensions, the closed, blue lines are deformed:A. loops B. spheresC. cylinders D. disks

Clicker Question 2In three dimensions, the elements of the field contour aresections of:A. loops B. spheresC. cylinders D. disks

Answers

1B2C

Class 16Today, we will:• learn what a capacitor is.• learn the definition of capacitance.• find the electric field and voltage inside a parallel-plate capacitor.• find the capacitance of the capacitor.• learn that a dielectric is a material with polar molecules.• learn how dielectrics increase capacitance.• find the energy stored in a capacitor and in the electric field.

Clicker Question 1A 4μF capacitor with a plate separation d is charged by connecting it to a 6 V battery. The battery is disconnected and the plates separated to 2d. Thenew capacitance and voltage are:

A. 8 μF and 12 V.B. 8 μF and 3 V.C. 2 μF and 12 V.D. 2 μF and 3 V.E. Nothing changes. d

AC

A

QE

0

0

Clicker Question 2

When compared to a capacitor with no dielectric, adding a dielectric

A. always increases capacitance.B. sometimes increases capacitance.C. never increases capacitance.

Answers

1C2A

Class 17Today, we will:• learn how to combine capacitors in series and parallel• find that circuits RC circuits have charges and currents that depend on exponential functions• learn the meaning of the exponential time constant• find that the exponential time constant for an RC circuit is τ=RC

Clicker Question 1

What is the equivalent capacitance of these three capacitors?

F3 F3 F3

FE

FD

FC

FB

FA

12.

9.

6.

3.

1.

Clicker Question 2What is the equivalent capacitance of these three capacitors?

F3

FE

FD

FC

FB

FA

12.

9.

6.

3.

1.F3

F3

Clicker Question 3

e

1

What is the time constant of the green (middle) curve?A. 1 s B. 2 s C. 3s D. 4s E. 5 s

Answers

1A2D3C

Class 18Today, we will:• learn the definition of a Gaussian surface• learn how to count the net number of field lines passing into a Gaussian surface• learn Gauss’s Law of Electricity• learn Gauss’s Law of Magnetism

Clicker Question 1What is the net number of field lines passing through the Gaussian surface?

A. -8B. -4C.0D.+4E. +8


A. -8B. -4C.0D.+4E. +8


A. -8B. -4C.0D.+4E. +8


A. -8B. -4C.0D.+4E. +8


A. -8B. -4C.0D.+4E. +8


A. -8B. -4C.0D.+4E. +8

Answers

1E2E3A4A5C6C

Class 19Today, we will:• learn how to use Gauss’s law and symmetry to find the electric field inside a shperical charge distribution• show that all the static charge on a conductor must reside on its outside surface• learn that why cars are safe in lightning but cows aren’t

Clicker Question 1The magnitude of the electric field E(r) outside a uniformly charged sphere (that means ρ is a constant) of radius a is best represented by which of the following graphs?

r

E(r)

a

A.

r

E(r)

a

B.

r

E(r)

a

C.

r

E(r)

a

D.

Clicker Question 2The magnitude of the electric field E(r) inside a uniformly charged sphere of radius a is best represented by which of the following graphs?

r

E(r)

a

A.

r

E(r)

a

B.

r

E(r)

a

C.

r

E(r)

a

D.

Answers

1B2A

Class 20Today, we will:• learn how integrate over linear, surface, and volume charge densities to find the total charge on an object• learn that flux is the mathematical quantity that tells us how many field lines pass through a surface

Clicker Question 1

A cylinder of length L and radius R has a charge

density where is a constant and z is the distance from one end. Find the total charge on the cylinder.

How do you slice the cylinder?

A. into cylindrical shells

B. into discs

C. into wedges

D. into rectangles

E. into rectangular prisms

4z

Clicker Question 2

dzRdV

dzrdV

rLdrdV

RdzdV

rdzdV

2

2

E.

D.

2 C.

2 B.

2 A.



What is the volume of each slice?

4z

Clicker Question 3



What are the limits of integration?

A. 0 to z

B. -z to +z

C. 0 to L

D. -L to +L

E. 0 to r

4z

Clicker Question 4

A sphere of radius R has a charge density where is a constant. Find the total charge on the sphere.

How do you slice the sphere?A. into discs, sliced in the x-direction.B. into discs, sliced in the y-direction.C. into discs, sliced in the z-direction.D. into spherical shells.E. into wedges.

r

Clicker Question 5


What is the volume of each slice?

r

drrdV

dzrdV

drrdV

drRdV

rdrdV

3

2

2

2

3

4 E.

D.

4 C.

4 B.

2 A.

Clicker Question 6


What are the limits of integration?A. 0 to RB. 0 to rC. –R to +RD. –r to +rE. all of the above

r

Answers

1B2E3C4D5C6A

Class 21Today, we will:• learn how to use Gauss’s law to find the electric fields in cases of high symmetry

• insdide and outside spheres• inside and outside cylinders• outside planes

Clicker Question 1

Gauss’s law states:

The Gaussian surface we choose:

A. can be any surfaceB. can be any closed surfaceC. can be only an element of a field contourD. can be only an element of a field contour

where the magnitude of the E field is the same everywhere on the surface.

0encq

EA

Clicker Question 2


In this equation, A represents:

A. the surface area of the charged object.B. the surface area of the Gaussian surface.C. the surface area of Mars.

0encq

EA

Clicker Question 3


In this equation, qenc always represents:

A. the total charge of the object.B. only the charge enclosed within the Gaussian

surface.C. the charge of an electron.D. the charge off an electron.

0encq

EA

Answers

1D2E3C

Class 22Today, we will:• learn the meaning of an Amperian loop• learn how to count the number of perpendicular surfaces pierced by a line• learn Ampère’s law: the net number of perpendicular surfaces pierced by an Amperian loop is proportional to the current passing through the loop• find how Ampère’s law and symmetry show that the magnetic field inside a hollow wire is zero• learn that the number of pierced surfaces is mathematically represented by the line integral.

Clicker Question 1

What is the net number of surfaces pierced by this Amperian loop?

A. -16B. -8C.0D.+8E. +16

Clicker Question 2

What is the net number of surfaces pierced by this Amperian loop?

A. -16B. -8C.0D.+8E. +16

Answers

1E2C

Class 23Today, we will use Ampere’s law to find the magnetic fields• inside and outside a long, straight wire with radial charge density• of a plane of wires• of a solenoid• of a torus

A wire of radius R has current density . Find the magnetic field inside the wire.What is the correct expression for the ℓ in the line integral?

2rj

R

r

R

r

2.D

2.C

.B

.A2

2

E. None of the above.

Clicker Question 1

A wire of radius R has current density . Find the magnetic field inside the wire.What is the correct expression for ?

2rj

drrridrrri

drrridrrri

R

enc

r

enc

R

enc

r

enc

0

22

0

22

0

2

0

2

4.D 4.C

2.B 2.A

enci


Clicker Question 2

3)(.D

3)(.C

4)(.B

4)(.A

3

0

3

0

4

0

3

0

RrB

rrB

r

RrB

rrB


A wire of radius R has current density . Find the magnetic field inside the wire.

2rj

Clicker Question 3

3)(.D

3)(.C

4)(.B

4)(.A

3

0

3

0

4

0

3

0

RrB

rrB

r

RrB

rrB


A wire of radius R has current density . Find the magnetic field outside the wire.

2rj

Clicker Question 4

Answers

1C2A3A4B

Class 24Today, we will use direct integration to find• electric fields of charged rods and loops• electric potentials of charged rods and loops• magnetic fields of current-carrying wire segments and loop segments (Biot-Savart law)

Clicker Question 1Are you here?

A.YesB. No

Clicker Question 2Are you still here?

A.YesB. No

Answers

1A2A

Class 25Today, we will:• learn the definition of divergence in terms of flux.• learn the definition of curl in terms of the line integral.• • find the gradient, divergence, and curl in terms of derivatives (differential operators) • write Gauss’s laws and Ampere’s law in differential form• work several sample problems

Clicker Problem 1You know both the electric and magnetic fieldsin a region of space. If you wish to find the volume charge density, you could use the differential form of

A. Gauss’s law of electricityB. Gauss’s law of magnetismC. Ampere’s lawD. Faraday’s lawE. Coulomb’s law

Clicker Problem 2

zxy

yxj ˆ12

),(0

Which picture best describes the current?Take red to be out of the screen and blue to be into the screen.

x

y

x

y

x

y

x

y

A B C D

Answers

1A2B

Class 27Today we will:• learn the definitions of electric and magnetic dipoles.•find the forces, torques, and energies on dipoles in uniform fields.•learn what happens when we put dipoles in nonuniform fields.

B

A

Clicker Question 1

At what angle θ is the torque on the dipolemaximum?

A. 0° B. 45° C. 90° D. 135° E. 180°

B

A

Clicker Question 2

At what angle θ is the potential energy ofthe dipole maximum?

A. 0° B. 45° C. 90° D. 135° E. 180°

Answers

1C2E

Class 28Today we will:• define magnetization and magnetic susceptiblity• learn about paramagnetic, diamagnetic, and ferromagnetic materials• learn about the opposing effects of domain alignment and thermal disalignment• learn how to understand hysteresis curves• characterize ferromagnetic materials in terms of residual magnetization and coercive force

Clicker Question 1

If this sphere is uniformly charged, it must be

A. positiveB. negativeC. neutral

N

S

Answers

1A

Class 29Today we will:•learn about threads and stubs of accelerating point charges.• learn that accelerating charges produce radiation (except in quantum mechanics).• learn the characteristics of radiation fields.

Clicker Question 1

If a charged particle has velocity in the +x direction, but acceleration in the –x direction:

A.the threads get smaller in timeB.the threads get larger in timeC. I don’t want to think about it, it’s almost Thanksgiving.

Clicker Question 2


A.the threads become perpendicular to the head lineB.the threads become parallel to the head line

Clicker Question 3


A.the direction of the thread is the same as when the particle’s acceleration is in the +x directionB.the direction of the thread is in the opposite direction to that when the particle’s acceleration is in the +x direction

Answers

1B2A3B

Class 30Today we will:•learn how accelerating charges affect circuits in significance ways•learn about induced electric fields•learn about induced magnetic fields and displacement current•learn Faraday’s Law•learn Maxwell’s Term of Ampere’s Law

Clicker Problem 1

ia

P

R

What is the direction of the electric acceleration field?A.rightB.leftC.inD.outE.up

Clicker Problem 2

ia

P

R

What is the direction of the magnetic acceleration field?A.rightB.leftC.inD.outE.up

Clicker Problem 3

ia

P

R

What is the direction of ? A. rightB. leftC. inD. outE. up

BE

Answers

1B2D3E

Class 31Today we will:• learn about EMF• learn how Faraday’s law works• learn Lenz’s Law and how to apply it

Clicker Question 1

B

vv

What happens if all sides of the loop move together?A. Current flows.B. Current doesn’t flow.

Clicker Question 2

• The external B is into the screen and is constant.

• A copper wire is placed in the field and rotated about the axis shown. In what direction is the induced current?

A.cwB.ccwC.depends on thedirection of rotation

x x x x

x x x x

x x x x

x x x x

externalB

Answers

1B2A

Class 32Today we will:• work several Faraday’s law problems• learn about Eddy currents

Class 32No new questions…

Class 33Today we will:•learn how motors and generators work•learn about split commutators and their use in DC motors and generators

Clicker Question 1

The flux through the loop is:

A

B

cos D.

cos C.

cos B.

A.

AB

A

B

BA

B

B

B

B

Clicker Question 2

If we rotate the handle with angular speed ,

A

B

/ C.

/ B.

A.

t

t

t

Clicker Question 3

If we rotate the handle with angular speed ,

the EMF is:

A

B

tBA

tBA

D

tBA

tBA

tBA

sin E.

sin .

sin C.

sin B.

cos A.

Answers

1D2A3B

Class 34Today we will:•learn about inductors and inductance•learn how to add inductors in series and parallel•learn how inductors store energy•learn how magnetic fields store energy•learn about simple LR circuits

Clicker Question 1

The direction of induced current will beA.always opposite the directionof the current from the battery.B. always in the direction ofthe current from the battery.C. possibly in either direction. V

R

L

N

Clicker Question 2

The inductive time constant will be proportional to

A. LRB. L/RC. R/LD. 1/(LR)

Answers

1C2B

Class 35Today we will:•learn more about LR circuits•learn the LR time constant•learn about LC circuits and oscillation•learn about phase angles

Clicker Question 1

The voltage around the circuit loop at any given time must be:

A. positiveB. negativeC. zero

V

R

L

Clicker Question 2If the current is

decreasing, the inductor will

A. cause the current to decrease faster

B. cause the current to decrease more slowly

C. not affect the rate the current decreases

V

R

L

2

1

Answers

1C2B

Class 36Today we will:•learn about phasors•define capacitive and inductive reactance•learn about impedance•apply Kirchoff’s laws to AC circuits

The phasor to the right represents:

30cos3

30sin3

30sin7.2

60sin5.1A.

B.

C.

D.

E. None of the above

Clicker Question 1

Which of the following is a phasor diagram for a capacitor, and inductor, and a resistor in series?Blue is voltage, red is current.

A. B.

C. D.

Clicker Question 2

Answers

1C2C

Class 37Today we will: • study the series LRC circuit in detail.• learn the resonance condition• learn what happens at resonance• calculate power in AC circuits

What is the same for each element in the circuit?

A.The magnitude of the voltageB.The magnitude of the currentC.The current phasorD.The voltage phasor

Clicker Question 1

R

L

i

C

0

Answers

1C

Class 38

Today we will: • find out how transformers work• learn about how electrical power is generated and delivered to our homes.

Clicker Question 1

A transformer has 100 turns in its primary coil and 200 turns in its secondary coil. The voltage across the primary coil is 12.0 V. The voltage across the secondary coil is:

A. 3.0 VB. 6.0 VC. 12.0 VD. 24.0 VE. 48.0 V

Clicker Question 2A step up transformer provides greater voltage in the primary and the secondary. This implies that

A. energy is not conserved in electrical circuits.B. energy is not conserved in transformers.C. the secondary cannot provide as much current as the primary.D. the secondary can provide more current than the primary.

Answers

1D2C

Class 39

Today we will: • learn about wires used in homes• learn how switches and outlets are wired• learn how to wire a 3-way switch• find out about safety devices: grounds, GFCI’s, and AFCI’s

Clicker Question 1

down down

If one switch is up and the other is down:A. the light is off.B. the light is on.C. It depends on which switch is up and which is down.

Clicker Question 2

big

resistance

small

resistance

Most of the current flows:

A. through the ground wireB. through youC. through the toastD.you are toast

Answers

1A2A

Class 40

Today we will: • review basic characteristics of waves• introduce definitions of wave terminology• show how Maxwell’s Equations predict electromagnetic waves• discuss the spectrum of electromagnetic radiation• learn how radio antennas send and receive signals

Clicker Question 1

If a wave has a wavenumber of k=4, what is its wavelength?

A. π/4

B. π/2

C. π

D. 2π

E. 4π

Clicker Question 2What is the wavelength of an FM radio wave that has a frequency of 100 MHz?

A. 3 mB. 3 cmC. 3 mmD. 3 μmE. 3 nm

Answers

1B2A

Class 41

Today we will: • learn how digital information is transmitted on electromagnetic waves • learn the meaning of polarization• learn about polarized light and its applications

A

B

C

DRed is E, blue is B.

Which figure best represents the wave along the z axis?

Clicker Question 1

Clicker Question 2

Unpolarized light passes through1)a polarizing filter2)a second polarizing filter at 45° with respect

to 1.3)a third polarizing filter at 45° with respect to 2.Does any light emerge?A. yesB. no

Answers

1C2A

Documents

Class 2