Unit 4B - Refraction of Light Flashcards
1
Q
Speed of Light (m/s)
A
- Air (vacuum): 3.00 x 10^8 (slightly higher than real life)
- Water: 2.26 x 10^8
- Acrylic: 1.76 x 10^8
2
Q
Refraction
A
The change in direction of light when it travels from one medium into another
3
Q
Angle of Refraction
A
Angle between the refracted ray and the normal
4
Q
Incident and Refracted Rays
A
Incident ray and refracted ray are on opposite sides of line (plane) that separates the two
5
Q
Rules of Refraction
A
- Light bends toward normal when SoL in second medium is less than in first medium.
- Light bends away from normal when SoL in second medium is greater.
- Incident, reflected and refracted rays on same plane
- Follows Reversibility of Light
6
Q
Partial Reflection and Refraction
A
- Light is both reflected off and refracted through a surface.
- Ex: Water, Glass
7
Q
Silvered Two-Way Mirror
A
- Glass that has a film coating allowing some incident light to be refracted but reflects much of incident light.
- Ex: Mirrored Sunglasses, Two-Way Glass Buildings
8
Q
Medium
A
- The material through which light is travelling
- Plural of medium: media
9
Q
Refracted Ray
A
The ray after crossing a boundary between media
10
Q
i, r and R
A
- i: Angle of incidence
- r: Angle of reflection
- R: Angle of refraction
11
Q
Fermat’s Principle
A
Light follows pathway taking least time
12
Q
Index of refraction
A
- Ratio of SoL in vaccum to SoL in different medium
- n = c/v = index of refraction
- c = 3.00 x 10^8 m/s
- v is the SoL in different medium
13
Q
Snell’s Law
A
- sinθ1/sinθ2 = n1/n2 = v1/v2
14
Q
Critical Angle
A
- Angle of incidence when angle of reflection is 90° to normal
- When critical angle is passed, total internal reflection occurs
15
Q
Visibility of Light: Water to Air
A
Even in clear water, only nearby underwater objects are visible to observer