Chapter 8- Light And Optics

Question 1

Visible light spectrum

Answer 1

400nm to 700nm

Question 2

Electromagnetic waves

Answer 2

Transverse waves oscillating with electric and magnetic fields that are perpendicular to each other

Question 3

Rectilinear propagation

Answer 3

When light travels through homogeneous mixture it travels in a straight line

Question 4

Reflection

Answer 4

Rebounding of incident light waves at the boundary of a medium (bounce off)

Question 5

Type of image for plane mirrors

Answer 5

Always virtual because light is in front but image looks like it’s behind the mirror

Question 6

Convex mirror

Answer 6

Everything appears smaller and further away. Diverging.

Question 7

Concave mirror

Answer 7

Everything appears bigger and closer. Converging.

Question 8

Focal point for spherical mirrors

Answer 8

f = r/2

Question 9

Mirror equation

Answer 9

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

Question 10

Image distance

Answer 10

Positive distance = real (in front of mirror)

Negative distance = virtual (behind mirror)

Question 11

Magnification

Answer 11

-i/o

Question 12

Refraction

Answer 12

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

Question 13

Speed of light in any medium besides a vacuum

Answer 13

It’s always less.

Question 14

Index of refraction

Answer 14

n = c/v
n- index of refraction of the medium
Always larger than 1 for anything besides air.

Question 15

Critical angle

Answer 15

sin -1 (n2/n1)

Question 16

Total internal reflection

Answer 16

A phenomena in which all the light incident on a boundary is reflected back into the original material. When angle of incidence is greater than the critical angle

Question 17

Lensmaker equation

Answer 17

1/f = (n-1) (1/r1 - 1/r2)

Question 18

Positive focal length and radii of curvature for mirror and lens

Answer 18

Converging

Question 19

Diverging lens or diverging mirror

Answer 19

Negative focal length and radii of curvature

Question 20

Power of lens

Answer 20

P = 1/f

f- focal length in meters

Question 21

Nearsighted vs farsighted lenses

Answer 21

Near- diverging lens

Far- converging lens

Question 22

Hyperopia

Answer 22

Farsightedness

Question 23

Myopia

Answer 23

Nearsightedness

Question 24

Spherical aberration

Answer 24

Blurring of periphery of an image as a result of inadequate reflection of parallel beams at the edge of a mirror or inadequate refraction of parallel beams at the edge of a lens.

Question 25

Location of dark fringes for single slit diffraction

Answer 25

a sin() = n(wavelength)

a- width of a slit

Question 26

Positions of dark fringes with two slits

Answer 26

d sin() = (n + 1/2)(wavelength)

d- distance between two slits

Question 27

Speed of light equation

Answer 27

c = f(wavelength)

Question 28

For single mirrors or lenses

Answer 28

All real images are inverted

Question 29

As light rays travel from one medium to another what changes

Answer 29

Wavelength only

Question 30

If a ray of light is traveling from one medium to another where it’s going from a low index of refraction to a higher one then what happens to the angle?

Answer 30

It gets smaller