Ch. 25

Question 1

When is there an induced current in a wire?

Answer 1

When the magnetic field in the coil is changing

Question 2

What happens to the charge carriers inside of a conductor when the conductor is moved through a magnetic field?

Answer 2

the charges experience a force (given by right hand rule) that creates charge separation and an electric field

Question 3

what creates a electric field inside of a moving conductor

Answer 3

magnetic force on charge carriers

Question 4

what is the motional emf

Answer 4

it describes the potential difference that it is induced due to the conductors motion in a magnetic field

Question 5

What happens to the magnetic field when a loop is tilted at an angle from the field

Answer 5

the effective area of the field is reduced so there is a change in the magnetic field called the magnetic flux

Question 6

what is the magnetic flux

Answer 6

it measures the amount of magnetic field passing through the loop of an Area A at an angle

Question 7

what is the unit of the magnetic flux

Answer 7

1 T*m^2

Question 8

when is a current created

Answer 8

when the magnetic flux through a loop changes

Question 9

in what direction will the induced current go?

Answer 9

it will go in the way that xreates a magnetic field that RESISTS the CHANGE in the flux

Question 10

if the magnetic flux changes in a way that increases the field downward, how will the induced current respond?

Answer 10

the current will go in a direction that creates a magnetic field pointing up, in order to resist the change in flux

Question 11

what is the magnitude of the induced emf

Answer 11

it is the rate of change of the magnetic flux through the loop

Question 12

what does a changing magnetic field cause? what does a changing electric field cause

Answer 12

a changing magnetic field creates an electric field

a changing electric field creates an induced magnetic field

Question 13

how fast do electromagnetic waves travel

Answer 13

at the speed of light

Question 13

if electric and magnetic fields can sustain themselves, free of charges or currents, what is formed

Answer 13

an electromagnetic wave

Question 14

what type of wave is light

Answer 14

an electromagnetic wave

Question 15

if you have a long wavelength, what frequency do you have

Answer 15

a low frequency

Question 16

if you have a short wavelength, what frequency do you have

Answer 16

a high frequency

Question 17

where is the plane of polarization aligned

Answer 17

it is aligned with the electric fiekd and can be oriented in any direction

Question 18

what do waves transfer

Answer 18

energy

Question 19

does the intensity of a plane wave vary with distance

Answer 19

no, it does not

Question 20

does the intensity of a spherical wave change with distance

Answer 20

yes

Question 21

how can unpolarized light ve transformed into polarized light

Answer 21

with a polarizing filter

Question 22

how do polarizers work

Answer 22

the parallel components of an unpolarized electric field are absorbed with the polarizer so only the perpendicular components emerge

Question 23

what is a crossed polarizer

Answer 23

when you have two polarizers that are 90 degrees from eachother (perpendicular) and they will block all light

Question 24

what type of nature do electromagentic waves have

Answer 24

they have particle-like nature with photon s