Light
Ray box
Log angles and see that sin i / sin r stays equal to n.
n = sin i / sin r
Apparatus
- Ray box
- Glass block
- Protractor measuring from the normal
Method
- Start with air into glass. Set n and the angle of incidence.
- Read the angle of refraction from the protractor.
- Log at least three angles. Look at the column sin i / sin r.
- Switch to glass into air and increase i until the ray reflects inside.
Do not look into a laser. This bench is a lamp and a glass block.
Incidence
40°
Refraction
25.4°
n
1.5
Critical angle
41.8°
Boundary
The ratio stays near n. Past the critical angle the refracted ray disappears.
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