Light and Optics

Question 1

What is the order of the electromagnetic spectrum from shortest wavelengths to longest?

Answer 1

Gamma rays - X rays - UV light - ROYGBIV - IR - Microwaves - FM Radio Waves - AM Radio Waves - Long radio waves

Question 2

What are electromagnetic waves?

Answer 2

transverse waves created by the electric field and magnetic field oscillating perpendicular to each other

Question 3

What is the speed of light (in a vacuum)?

Answer 3

c = 3.00 x 10^8 m/s

Question 4

What is the relationship between speed of light, frequency and wavelength?

Answer 4

c = f*lambda
c = speed of light

Question 5

What are the boundaries of the visible spectrum?

Answer 5

400 to 700 nm ish

Question 6

What is it called when light travels in a straight line?

Answer 6

rectilinear propagation

Question 7

What is reflection?

Answer 7

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

Question 8

What is the normal?

Answer 8

line drawn perpendicular to the boundary of a medium

Question 9

What is Law of Reflection?

Answer 9

theta1 = theta2 - degree of the incident angle is the same as that of the reflected angle

Question 10

What is a real image?

Answer 10

an image is real if the light converges at the position of the image

Question 11

What is a virtual image?

Answer 11

if the light only appears to be coming from the position of the image but does not actually converge there

Question 12

What is a plane mirror?

Answer 12

flat, reflective surfaces that always create virtual images

Question 13

What is the center of curvature?

Answer 13

is the point from the vertex of the mirror that is the radius length away - so center of the sphere if the mirror was a complete sphere

Question 14

Concave mirrors are called ______ mirrors and convex mirrors are called ______ mirrors.

Answer 14

converging; diverging

Question 15

What is the focal length?

Answer 15

focal length = radius of curvature/2

Question 16

What is the relationship between focal length, object distance, image distance, and radius of curvature with the mirror?

Answer 16

1/f = 1/o + 1/i = 2/r
f = focal length
o = distance between object and mirror
i = distance between image and mirror
r = radius of curvature

Question 17

If the image has a positive distance (i>0), it is a ____ image, which implies that the image is ______ of the mirror.

Answer 17

real; in front

Question 18

If the image has a negative distance (i<0), it is a ____ image, which implies that the image is ______ of the mirror.

Answer 18

virtual; behind

Question 19

What is the equation for magnification?

Answer 19

m = -i/o

Question 20

A negative magnification signifies an _____ image while a positive value signifies an ______ image.

Answer 20

inverted; upright

Question 21

If absolute value of m < 1, the image is _____ than the object; if the absolute value of m > 1, the image is ______ than the object?

Answer 21

smaller; bigger

Question 22

What is refraction?

Answer 22

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

Question 23

What is the equation for the index of refraction?

Answer 23

n = c/v
n = index of refraction of the medium
c = speed of light in a vacuum
v = speed of light in the medium

Question 24

What is Snell’s Law?

Answer 24

n1*sintheta1 = n2*sintheta2
1 = medium light is coming from
2 = medium the light is entering

Question 25

If the light travels to a higher index of refraction to a lower one, the refracted angle will be _____ than the incident angle.

Answer 25

larger

Question 26

What is the critical angle (thetac)?

Answer 26

when the refracted angle equals 90 degrees

Question 27

What is the total internal reflection?

Answer 27

a phenomenon in which all the light incident on the boundary is reflected back into the original material; angle of incidence greater than the critical angle

Question 28

What is the lensmaker’s equation

Answer 28

1/f = (n-1)(1/r1 -1/r2)
n = index of refraction of the lens material
r1 = radius of curvature of the first lens surface
r2 = radius of curvature of the second lens surface

Question 29

Equation for power of lens

Answer 29

P = 1/f

Question 30

What is a spherical aberration?

Answer 30

a blurring of the periphery of an image as a result of inadequate reflection of parallel beam sat the edge of a mirror or inadequate refraction of parallel beams at the edge of a lens

Question 31

What is dispersion?

Answer 31

when various wavelengths of light separate from each other

Question 32

What is chromatic abberation?

Answer 32

a dispersive effect within a spherical lens; results in rainbow halos

Question 33

What is diffraction?

Answer 33

refers to the spreading out of light as it passes through a narrow opening or around an obstacle

Question 34

Equation for position of dark fringe in a slit-lens system

Answer 34

a*sintheta = n*lambda
a = width of the slit
sin(theta) = angle between the line drawn from the center of the lens to the dark fringe and the axis of the lens
n = an integer indicating the number of the fringe
lambda = wavelength of the incident wave

Question 35

Equation for position of dark fringe in a multiple lens system

Answer 35

d*sintheta = (n +1/2)*lambda
d = distance between two slits
theta = angel between the line drawn from the midpoint between the two slits to the dark fringe and the normal
n = integer indicating the number of the fringe
lambda = wavelength of the incident wave

Question 36

What is plane polarized light?

Answer 36

light in which the electric fields of all the waves are oriented in the same direction