Light and Optics Flashcards
What is the order of the electromagnetic spectrum from shortest wavelengths to longest?
Gamma rays - X rays - UV light - ROYGBIV - IR - Microwaves - FM Radio Waves - AM Radio Waves - Long radio waves
What are electromagnetic waves?
transverse waves created by the electric field and magnetic field oscillating perpendicular to each other
What is the speed of light (in a vacuum)?
c = 3.00 x 10^8 m/s
What is the relationship between speed of light, frequency and wavelength?
c = f*lambda c = speed of light
What are the boundaries of the visible spectrum?
400 to 700 nm ish
What is it called when light travels in a straight line?
rectilinear propagation
What is reflection?
the rebounding of incident light waves at the boundary of a medium
What is the normal?
line drawn perpendicular to the boundary of a medium
What is Law of Reflection?
theta1 = theta2 - degree of the incident angle is the same as that of the reflected angle
What is a real image?
an image is real if the light converges at the position of the image
What is a virtual image?
if the light only appears to be coming from the position of the image but does not actually converge there
What is a plane mirror?
flat, reflective surfaces that always create virtual images
What is the center of curvature?
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
Concave mirrors are called ______ mirrors and convex mirrors are called ______ mirrors.
converging; diverging
What is the focal length?
focal length = radius of curvature/2
What is the relationship between focal length, object distance, image distance, and radius of curvature with the mirror?
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
If the image has a positive distance (i>0), it is a ____ image, which implies that the image is ______ of the mirror.
real; in front
If the image has a negative distance (i<0), it is a ____ image, which implies that the image is ______ of the mirror.
virtual; behind
What is the equation for magnification?
m = -i/o
A negative magnification signifies an _____ image while a positive value signifies an ______ image.
inverted; upright
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?
smaller; bigger
What is refraction?
the bending of light as it passes from one medium to another and changes speed
What is the equation for the index of refraction?
n = c/v n = index of refraction of the medium c = speed of light in a vacuum v = speed of light in the medium
What is Snell’s Law?
n1*sintheta1 = n2*sintheta2 1 = medium light is coming from 2 = medium the light is entering
If the light travels to a higher index of refraction to a lower one, the refracted angle will be _____ than the incident angle.
larger
What is the critical angle (thetac)?
when the refracted angle equals 90 degrees
What is the total internal reflection?
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
What is the lensmaker’s equation
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
Equation for power of lens
P = 1/f
What is a spherical aberration?
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
What is dispersion?
when various wavelengths of light separate from each other
What is chromatic abberation?
a dispersive effect within a spherical lens; results in rainbow halos
What is diffraction?
refers to the spreading out of light as it passes through a narrow opening or around an obstacle
Equation for position of dark fringe in a slit-lens system
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
Equation for position of dark fringe in a multiple lens system
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
What is plane polarized light?
light in which the electric fields of all the waves are oriented in the same direction
