Waves

Question 1

What is the relationship for magnification?

Answer 1

m = di/do

Question 2

On a plane mirror, what is the relationship between the angle of incidence and the reflected angle?

Answer 2

Θ1=Θ2

Question 3

On a mirror/lens, the focal point is half of what?

Answer 3

The radius of curvature (r).

Question 4

How is a real image created?

Answer 4

When two rays meet.

Question 5

How is a virtual image created?

Answer 5

Lines are reflected in a way so they appear to meet.

Question 6

What is the relationship between focal length, and image / object distance?

Answer 6

1/f = 1/di + 1/do

Question 7

When does an image become virtual in a concave mirror?

Answer 7

When the object is past the focal point

Question 8

Concave mirror: if a ray of light is parallel to the principle axis, where will it be reflected?

Answer 8

Through f

Question 9

Concave mirror: if a ray of light travels through f, where will it be reflected?

Answer 9

Parallel to the principle axis

Question 10

Concave mirror: if a ray of light travels through C, where will it be reflected?

Answer 10

Back through C

Question 11

Concave mirror: if a ray of light hits the center of the mirror, at what angle will it be reflected?

Answer 11

At the angle of incidence (mirror acts like a plane mirror in the center).

Question 12

If a virtual image is 2 cm behind the mirror, what value should you put into the lens equation?

Answer 12

Negative 2 cm (virtual quantities are negative)
Ignore with magnification

Question 13

How would you describe the focal length of a convex mirror?

Answer 13

Virtual (it is behind the mirror, technically doesn’t exist)

Question 14

Convex mirror: if a ray of light travels parallel to the principle axis, where will it be reflected?

Answer 14

As it it came from the virtual focal point.

Question 15

Convex mirror: if a ray of light travels toward the virtual focal point, where will it be reflected?

Answer 15

Parallel to the principle axis.

Question 16

If a ray hits the center of a convex mirror, what angle will it be reflected off at?

Answer 16

The same angle as the angle of incidence

Question 17

If light enters a more optically dense substance, in which direction will it bend?

Answer 17

Toward the medium

Question 18

If light enters a less optically dense substance, in which direction will it bend?

Answer 18

Away from the medium

Question 19

How do you calculate the refractive index of something (i.e. what is the equation)?

Answer 19

Refractive index = speed of light in vacuum/speed of light in object

Question 20

What is the primary relationship between angle and refractive index?

Answer 20

n1 sinΘ1 = n2 sinΘ2

Question 21

What is the relationship between refractive index and light speed?

Answer 21

n1 v1 = n2 v2

Question 22

What is the critical angle?

Answer 22

The angle at which a ray of light will experience total internal reflection

Question 23

What is total internal reflection?

Answer 23

When a ray of light is not refracted, but is reflected back into the object

Question 24

The critical angle can be seen as the point where the ray is reflected at 90 degrees (i.e. in the object). What is the formula for critical angle?

Answer 24

sinΘc= n2/n1

Question 25

Convex lens: if a ray travels parallel to the principle axis, where will it be refracted to?

Answer 25

Through the focal point.

Question 26

If a ray travels through the optical center of a lens, what will it’s path of travel be like?

Answer 26

Unchanged

Question 27

Convex lens: if a ray travels toward the focal point, where will it be refracted?

Answer 27

Parallel to the principle axis

Question 28

Concave lens: if a ray is traveling toward the focal point, where will it be refracted to?

Answer 28

Parallel to the principle axis.

Question 29

Concave lens: if a ray is traveling parallel to the principle axis, where will it be refracted?

Answer 29

As if it came from the focal point on the other side of the lens

Question 30

An image created by a concave lens is always…

Answer 30

diminished, upringht, and virtual

Question 31

for a convex lens, objects past f create…

Answer 31

virtual images

Question 32

What do waves transfer?

Answer 32

Energy (not matter)

Question 33

What is the expression for the velocity of waves

Answer 33

v=f (lambda)

Question 34

What is one attribute of a wave that never changes?

Answer 34

Frequency

Question 35

In refraction, there is a “big relationship”. what is it?

Answer 35

n2/n1 = v1/v2 = lambda1/lambda2 = sinΘ1/sinΘ2

Question 36

When is diffraction at it’s greatest extent?

Answer 36

When the gap equals the wavelength

Question 37

Why does refraction occur?

Answer 37

Because one part of a wave hits the slower substance before the other, slightly changing it’s overall trajectory.

Question 38

When a wave hits a boundary (like a change in medium), some energy is transmitted, while some is reflected. If a wave hits a thicker substance (in essence a fixed end), will the transmitted or reflected wave be inverted?

Answer 38

The transmitted wave will be uninverted, while the reflected wave will be inverted.

Question 39

What is the name of the phenomenon when waves pass through each other?

Answer 39

Superposition

Question 40

In interference patterns, what kind of interference do antinodal lines show?

Answer 40

Constructive interference

Question 41

In the two-mouthed harbour example used to explain interference patterns, what is the relationship between distance traveled by each wave where the waves are strong?

Answer 41

The difference between distance traveled between the waves from the two sources is an integer of a whole wavelength, so they arrive in phase.