Refraction

Real depth and Apparent depth

REAL AND APPARENT DEPTH

Apparent depth

Real depth

REFRACTIVE INDEX

REFRACTIVE INDEX = REAL DEPTH

APPARENT DEPTH

Eg:

REFRACTIVE INDEX OF WATER = 8m = 1.33

6m

Total Internal Reflection

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Phenomena Related to total internal Reflection

Problems

• A glass block 3.6 cm thick is placed over a stamp. Calculate the apparent height & the height through which image of stamp is raised. Refractive index of glass is 1.5 ?

• Answer:Height through which image is raised= (3.6 – 2.4)=1.2 cm.

• A block of glass has a critical angle of 45.0º. If light is passing from the glass into air, what is the index of refraction of the glass block?

• Find the critical angle of light passing from a diamond into air.

Arrange n1,n2 &n3 in descending order

• Speed of light in diamond = 120 000 000 m/s• Angle of incidence ‘i’ = 60 ̊ • Calculate the angle of refraction.

• Critical angle of glass = 49 ̊• Angle of incidence ‘i’ = 60 ̊ • Calculate the angle of refraction.

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• Speed of light in material Y = 2× m/s• Critical angle of material X = 49 ̊• The angle of refraction = 22• Calculate the angle of incidence.