Download CH15 Refraction READ NOTES Serway

PHYSICS
Name __________________________________________ Date _____________
Energy: Conservation and Transfer
Phy.
2.2
Analyze the
behavior of
waves.
Phy2.2.1 Analyze how energy is transmitted through waves, using the fundamental characteristics of
waves: wavelength, period, frequency, amplitude, and wave velocity.
Phy2.2.2 Analyze wave behaviors in terms of transmission, reflection, refraction, and interference.
Phy.2.2.3 Compare mechanical and electromagnetic waves in terms of wave characteristics and behavior
(specifically sound and light).
Text Reference: Physics (Serway) Chapter 15
Refraction
Look at the intro-photo on pages 560-561 & read about rainbows. A rainbow occurs when sunlight is _______
as it passes from air to water and then from water to air.
15-1 Refraction
REFRACTION OF LIGHT
Look at the tiny image of the flower that appears in the water droplet in Figure 15-1. The flower can be seen in the
background of the photo. Why does this flower look different when viewed through the droplet? This phenomena
occurs because light is ___________________ at the boundary between the water and the air around it.
Define refraction:
If light travels from one transparent medium to another at any angle other than straight on (parallel to the line normal
to the surface), the light ray changes direction when it meets the _________________________.
As in the case of reflection, the angles of the incoming and refracted rays are measured with respect to the
_____________________.
For studying refraction, the normal line is extended _________________ the refracting medium as shown in Figure 15-2.
The angle between the refracted ray and the normal is called the ________________________________________, θr.
For refraction, the angle of incidence is θi.
Refraction occurs when light’s velocity ____________________________.
Glass, water, ice, diamonds, and quartz are all examples of _____________________________ media through which
light can pass. The speed of light in water is ____________________ than it is in air. And the speed of light in glass is
______________________ than the speed of light in water.
When light moves from a material in which the speed is higher to a material in which its speed is lower, such as from air
to glass, the ray is bent ________________________________________________________________________ as
shown in Figure 15-2(a).
If the ray mives from a material in which its speed is lower to one in which its speed is higher, as in Figure 15-2(b), the
ray is bent ___________________________________________________________________________________.
If the incident ray of light is parallel to the normal, then _________________________________________.
Note that the path of a light ray that crosses a boundary between two media is _________________________________.
If the ray in Figure 15-2(a) originated outside the glass block, it would follow the same path as shown in the figure, but
the reflected ray would be ________________________ the block.
Draw (or trace) both parts of Figure 15-2:
Refraction can be explained in terms of the _____________________ model of light.
Study Figure 15-3 as a practical analogy of this principle.
THE LAW OF REFRACTION
An important property of transparent substances is the index of refraction.
Write the definition of INDEX OF REFRACTION in words, long & short equation forms:
From this definition we see that the index of refraction is a __________________________ number that is always
greater than ____ because light always travels slower in a substance than in a _______________________.
Read the Did You Know?
Write this equation also:
(Ask for help if you cannot understand why this equation has two forms.)
Study Table 15-1 Indices of refraction for various substances. Compare this table to your Formulas Sheet table.
Note that the index of refraction of air is nearly that of a vacuum. For simplicity, use the value of n = 1.00 for air when
solving problems.
Objects appear to be in different _________________________ due to refraction.
Explain why:
________________________________ affects the index of refraction.
Explain why:
Snell’s law determines the ____________________________ of refraction.
In 1621, Willebrod Snell experimented with light passing through different media. He developed the relationship which
bears his name.
Write SNELL’S LAW equation & identify each term:
Study SAMPLE PROBLEM 15A Snell’s law; Try PRACTICE 15A problems.
15-2 Thin Lenses = NOT REQUIRED (extra credit)
15-3 Optical Phenomena
TOTAL INTERNAL REFLECTION
Define total internal reflection:
Define critical angle:
Sketch or trace Figure 15-12(b)
Write the CRITICAL ANGLE equation & identify each term:
Study SAMPLE PROBLEM 15C; Try PRACTICE 15C Critical angle.
____________________________________________ can guide light over a long distance.
Explain how this light pipe works:
Sketch or trace Figure 15-13(b)
Refracted light produces ______________________________________________
DISPERSION
Write the definition of dispersion:
White light passed through a _____________________________ produces a visible ____________________________.
Sketch or trace Figure 15-15:
_____________________________ are created by _____________________________ of light in water droplets.
Summarize how rainbows are formed by writing the Figure 15-16 caption below: