Reflection & Refraction Flashcards
Angle of incidence = angle of reflection on a smooth surface
yes
Specular reflection vs diffuse reflection
smooth surface –> perfect reflection (think light glare of apple) vs rough surface –> reflection in all kinds of diff direction (think color of apple)
What’s Snell’s Law?
n1sin(theta)1 = n2sin(theta)2
What’s the formula of refraction index and their values for vacuum, water and air?
n = c/v (speed of light/vel)
water: n = 1.33, air: n = 1.0003, vacuum: n = 1
How do you know which angle to work for?
look for the angle that’s from normal line
What’s the critical angle?
greatest angle of incidence to give 90 degree refraction (so you don’t get total internal reflection, but you can’t escape old medium either)
What’s total internal reflection?
When the angle of refraction is so big that it doesn’t refract in a new medium –> it just reflects back into the old medium
The bigger the refraction index…
the bigger the refraction
What’s the relationship b/w wavelength and refraction index?
smaller wavelength –> bigger refraction index –> bends more. Wavelengths change as light enters a diff medium
How do you know if light will reflect vs refract?
Hits a smooth surface or surpasses critical angle b/w mediums vs moving from medium to another
Rectilinear propagation
When light travels thru a homogenous medium in a straight line
Why do plane mirrors always create virtual imgs?
Parallel rays always reflect right off —> no converging or diverging reflected rays
Relationship between n1 and n2
When n1>n2, light bends away nml line. When n1 < n2 —> light bends toward nml line.
Spherical aberration vs chromatic aberration vs dispersion
Blurring of periphery due to inadequate reflection of parallel beams at edge of mirror or inadequate refraction of parallel beams at edge of lens vs dispersive effect within a lens vs when various wavelengths of light separate from e/o (ex: white light splitting into different colors thru a prism; this can happen during diffraction or refraction)
