Chapter 8 - Light + Optics

Question 1

Réflection

Answer 1

The rebounding of incident light waves at the boundary of a medium

Theta1 = theta2

Question 2

How are reflected angles measured?

Answer 2

From the normal

Question 3

What is the equation for focal length?

Answer 3

F = r/2

Question 4

What equation is used for distance of focal length, image, and object?

Answer 4

1/f = (1/o)+(1/i) = 2/r

Question 5

Is the image real or virtual if it has a positive distance?

Answer 5

Real

Question 6

How do you calculate magnetification?

Answer 6

M = - i/o

Question 7

How can you tell if image is upright or inverted?

Answer 7

+ value is upright

- value is inverted

Question 8

Remember UV and IR

Answer 8

Upright always virtual

Inverted always real

Question 9

Réfraction

Answer 9

Bending of light as it passes from one medium to another and changes speed

Question 10

Snells law

Answer 10

n = c/v

C = speed of light in vacuum
V = speed of light in the medium

Question 11

What is index of refractino of a vacuum

Answer 11

1

Air : 1.0003

Water: 1.31

Glass: 1.48 - 1.93

Question 12

Snells law

Answer 12

N1sinø1=n2sinø2

Question 13

When light enters medium with higher index of refraction, which direction does it bend?

Answer 13

Toward normal

If lower IOR, bends away from normal

Question 14

What is power?

Answer 14

P = 1/f

+ for converging
- for diverging

Question 15

What is hyperopia? myopia?

What corrective lens would be used for each?

Answer 15

Hyperopia: farsightedness
- Converging lens

Myopia: nearsightedness
- diverging lens

Biofocal has both! Très cool!

Question 16

How are power and multiple lens systems compounded?

Answer 16

1/f = 1/f1 + 1/f2 ….

P = p1 + P2 + P3…..

Example: contact lenses

Question 17

How do contact lenses work?

Answer 17

Cornea of the eye (converging lens) is in contact with a contact lens (either converging or diverging) and their powers are added

Question 18

What happens if multiple lenses are not in contact?

Answer 18

The image from the last lens becomes the object of another lens.

Ex: microscopes and telescopes

M = m1 x m2 x m3…

Question 19

What has smaller wavelength red or violet?

Answer 19

Violet has a smaller wavelength than red light and so is bent to a greater extent