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7 Refraction.notebook March 09, 2017
Where can we see refraction of light?
Define
The change in direction of waves (light) at the boundary between two different media.
The waves must hit the new medium at an angle for direction to change
From the 2D waves lab
7 Refraction.notebook March 09, 2017
Imagine a car driving towards the sea at an angle. When the first front wheel hits the water, the resistance makes that wheel turn slower than the other wheel. As a result, the car rotates until the second wheel is also in the water. Then both wheels turn at the same time. The car stops rotating.
Pg 488
When the car comes out of the water, the righthand wheel turns faster than the left, so the car rotates again. When both wheels are out of the water, the car stops rotating and moves forward. This is exactly what happens when a light ray hits a denser medium.
7 Refraction.notebook March 09, 2017
The refractive power of a substance can be found by comparing the speeds of light through the substances.In fact the ratio of these speeds tells you the refractive index of the substance.
cv= n
n = index of refraction
c = speed of light in a vacuum(3.00 x 108 m/s)
v = speed of light in the substance
Light travels at 1.95×108 m/s in a substance. what substance is it?
7 Refraction.notebook March 09, 2017
Light Bending
incident raynormal
glassair
θR
θi
refracted ray
incident ray
normal
θi
Reflected ray
θr
Reflection Refraction
n1sin θ1 = n2 sin θ2
θ2 angle of refraction for substance 2
θ1 angle of incidence for substance 1
n2 index of refraction for substance 2
n1 index of refraction for substance 1
7 Refraction.notebook March 09, 2017
AirGlass
EX
Water