Optics - Semester One Flashcards
What is Snell’s law?
Sinø1 / Sinø2 = n2 / n1
Equation for finding focal length from curvautre?
f = R / 2
What is the thin lens equation?
1 /s + 1 /s’ = 1/f
Equation to find size and magnification.
m = y’/y = - s’/s
Power P of a lens is…
P = 1 / f
Lens makers eqaution 1/f =
(n - 1) (1 / R1 - 1 / R2)
Through a piece of glass, will blue or red refract to a higher angle more?
Blue, Because red is faster in glass
For light, what happens above the critical angle?
No exit ray
Total internal reflection
Light can only be refelcted
Equation to find speed of light in a medium n =
n = c / v
What two assumptions does the ideal gas law make about a gas?
The molecules of the gas have neglible size
They do not interact with each other
Define the term angular magnification
Angular magnification is the ratio of the angular size of the object seen through the optical instrument θ’, to the angular size of the object seen with the unaided eye θ
A lens that is thicker at its centre than at its edges is a…
Converging lens with positive f
A lens that is thicker at its edges than at its centre is a…
Diverging lens with negative f
Optics
Object on the incoming side of surface, s is…
s > 0
Real Object
Optics
Image on the outgoing side of surface, s’ is…
s’ > 0
Real Image
Optics
Centre of curvature is on outgoing side side of surface, R is…
R > 0
When image is erect hehe, m is…
m > 0
When image is inverted, m is…
m < 0
Equation to relate wavelength to refractive index…
na λa = nb λb
Anti-Reflective coating…
Thickness of coating t =
t = λfilm /4
