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Unit Three

OPTICS

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Chapter 11

Refraction of Light

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Objectives

1

Refraction of Light

2

Laws of Refraction

3

Total Internal Reflection

4

Dispersion of White Light

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Refraction of Light

Refraction:

Is a sudden change in the direction of light, when the light crosses the surface separating two transparent mediums.

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Laws of Refraction

First Law of refraction:

The incident ray, the refracted ray, and normal to the surface of separation of two media, all are in the same plane of incidence.

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Laws of Refraction

Second Law of refraction (Snell’s Law):

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Laws of Refraction

Example 1:

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Laws of Refraction

Solution of Example 1:

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Laws of Refraction

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Total Internal Reflection.

How to calculate limiting angle??

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Dispersion of white Light.

When the light passes through the prism, we observe on a screen a series of colors as indicated in the figure.

Direct a beam of white light to the surface of a glass prism.

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Dispersion of white Light.

We notice that:

White light contains series of colors we see on the screen.

The prism has dispersed the colors that constitute white light.

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Grade 10 Solving problems physics

A luminous ray, propagates in air, and hits the surface of separation (air –water) with an angle of incidence iair. When the incident angle is iair =40, the refracted angle is iwater = 29.

Calculate the index of refraction of water.
Calculate the deviation of the corresponding incident ray in air iair =45.
The light ray propagates in water, hits the surface of separation (air-water) with iwater =60.

Study the path of the ray.

Exercise 1:

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Grade 10 Solving problems physics

Calculate the index of refraction of water.

Solution of Exercise 1:

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Grade 10 Solving problems physics

Solution of Exercise 1:

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Grade 10 Solving problems physics

Solution of Exercise 1:

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Grade 10 Solving problems physics

Exercise 2:

A rectangular medium of index n is in

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Grade 10 Solving problems physics

Solution of Exercise 2:

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Grade 10 Solving problems physics

Draw a figure showing the light till it emerges out AC.

Solution of Exercise 2:

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Grade 10 Solving problems physics

Solution of Exercise 2:

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Grade 10 Solving problems physics

Solution of Exercise 2:

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Grade 10 Solving problems physics

Solution of Exercise 2:

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Grade 10 Solving problems physics

Exercise 3:

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Grade 10 Solving problems physics

Solution of Exercise 3:

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Grade 10 Solving problems physics

Solution of Exercise 3:

The ray refracted away from the normal.

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Grade 10 Quiz in Physics Time: 15min

Quiz in physics (5points)

Chapter 11: refraction of Light

Time: 15 min

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Grade 10 Quiz in Physics Time: 15min

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Grade 10 Quiz in Physics Time: 15min

Show that IJ undergoes refraction with angle of refraction to be calculated. (1.5 point).
Show on a figure the path of ray SI till it leaves the prism. (1 point).
Deduce the total deviation of SI. (0.5 point).

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Grade 10 Quiz in Physics Time: 15min

Solution of Quiz:

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Grade 10 Quiz in Physics Time: 15min

Solution of Quiz:

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Grade 10 Quiz in Physics Time: 15min

Solution of Quiz:

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Grade 10 Quiz in Physics Time: 15min

Solution of Quiz:

Show on a figure the path of ray SI till it leaves the prism. (1 point)

See the figure.

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Grade 10 Quiz in Physics Time: 15min

Solution of Quiz:

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End of Chapter 11