# Refraction at a plane surface

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• Created by: Frankie
• Created on: 03-04-13 13:16
What happens when a wave moves from one medium to another?
The wave changes speed which can lead to a change in direction
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Refraction
The change in direction when a wave moves from one medium into another
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Speed of light
3x10^8 ms^-1
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What changes/ stays the same when refraction happens?
Frequency stays the same but wavelength and speed change
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A ray of light refracts ????? the normal when it slows down
Towards
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A ray of light refracts ????? from the normal when it speeds up.
Away
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The greater the change in speed the more the ray ..........
Deviates from its original path.
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In a vacuum all waves.........
Tavel at the same speed - c
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As waves pass through matter they ......
Slow down to a new speed - v
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The refractive index - n - of a material is ........
The ratio of the speed of light in a vacuum to its speed in a material
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n =
n = speed of light in a vacuum / speed of light in material
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n =
n = c/v
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Refractive index - n - or ......
Absolute refractive index
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If waves hit a boundary between media at an angle .....
The change in speed causes a change in direction
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The 'normal' to a medium at an angle is always.......
Perpendicular to the surface of the medium
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Value of refractive index is always greater than 1 because.....
Light always travels faster in a vacuum than in another material.
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Unit of refractive index??
Doesn't have be b/c it's a ratio
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The higher the value of the refractive index, the..........
the more the light is slowed down and the greater its deflection
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Materials with a high value of refractive index are said to be..
Optically dense
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What determines how much a ray will be refracted?? ie. the relative refractive index
The relative speed of light in each of the materials.
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Relative refractive index (notation)?
1n2
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What is the relation between absolute refractive index - n - and relative refractive index - 1n2 ?
Relative refractive index is refractive index of a medium with respect to another medium Absolute refractive index is refractive index of a medium with respect to vacuum.
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1n2 = (Words)
Speed of light in medium 1 / speed of light in medium 2
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1n2= (Notation)
v1/v2
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Relative refractive index=
n2/n1
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1n2
= 1/2n1
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In order to calculate the relative refractive index we need to know......
The absolute refractive indices or two materials n1 and n2
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## Other cards in this set

### Card 2

Refraction

#### Back

The change in direction when a wave moves from one medium into another

Speed of light

### Card 4

#### Front

What changes/ stays the same when refraction happens?

### Card 5

#### Front

A ray of light refracts ????? the normal when it slows down

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