SCIENCE LOVER

1. Refraction through
Plane Parallel plates

2. When a ray light passes through a flat slab of a
transparent material, such as a piece of glass plate,
the emergent ray is parallel to the incident ray but
displaced from it. Consequently, when we look at
any object through a glass plate, we see it slightly
displaced in position but unchanged.

4. Snell’s Law
When ray of light travels from air into
glass, it bends towards the normal lines.
Sin1n1=sin2n2

5. Sample problem
A ray of light from air is incident on a glass plate
(n=1.52) at 30.0 degrees and emerges back into the
air. Find angle A, and angle B?

6. A
B

7. Solution:
Given: n of glass = 1.52
n of air= 1.00
Formula
Sin2=sin1n1/n2
Sin2=(sin30)(1.00)/1.52
Sin2=19.2

8. Sin2=(sin30)(1.00)/1.52
Sin2=19.2
Sin2=(sin19.2)(1.52)/1.00
Sin2=30

9. Refraction by a prism

10. The prism normally used in refracting light is a triangular
solid with two solid refracting surfaces. The angel between
these two refracting surfaces is called a Refracting angle of a
prism.
When a ray light from air enters the prism at the first
refracting surfaces, the refracted ray is bent toward the normal
because the material of the prism is optically denser than air.
As it emerges in the second surfaces the light is bent away
from the normal.
The angle between the extension of the incident ray and the
emerging ray is called the Deviation angle.

11. A ray light in air passes into normal glass. The
glass is in the shape of an equilateral triangle
(prism) the angle of the ray (from the normal
line) in air is 50degress. Calculate the angle of
the ray in the glass?