KCL Section 4: Refraction Flashcards
The refractive index is?
The refractive index is a ratio which tells you how much the speed of light will change (and therefore how much light will change direction) when it arrives at a boundary between two mediums.
The speed of light in a certain glass is 1.8 x 108 ms-1. What is the refractive index of the glass?
1.7
The speed of light in air is 2.9979 x 108 ms-1. What is the refractive index of the air?
1.00
The speed of light in a certain plastic is 2.08 x 108 ms-1. What is the refractive index of the plastic?
1.44
The speed of light in a plastic is 1.92 x 108 ms-1. What is the refractive index of the plastic?
1.56
The speed of light in water at 25oC is 2.26 x 108 ms-1. What is the refractive index of the water?
1.33
The refractive index of diamond is 2.4. What is the speed of light in diamond?
1.3 x 108 ms-1
The refractive index of an oil is 1.518. What is the speed of light in the oil?
1.98 x 108 ms-1
The refractive index of hexane is 1.37. What is the speed of light in hexane?
2.19 x 108 ms-1
What is the angle of refraction when a light ray passes from water (n1 = 1.33) into glass (n2 = 1.50), hitting the interface between the two at an angle of 48° to the normal?
41.2°
The speed of light is 3x10^8 in water and 2.3x10^8
1) Calculate the refractive index for light passing from air to water, air to glass and from water to glass.
- 3
- 5
- 2
What is refraction?
Refraction is a change in wave speed when the wave moves from one medium to another. There is a corresponding change in wave direction.
What is partial transmission
When waves travel from one medium to another some light is refracted, but some will be reflected (for example, you can usually see a faint reflection of yourself in windows)
