Review for Refraction/Reflection Test

Enter each group member's AIDE letters


Enter your class period (1-8)

Vocabulary. Match the correct definition to each word.

		1. excitation	A. q_i = q_r
		2. refraction	B a bundle of radiant energy (E = hf), the particle nature of light
		3. mirage	C. produces diffuse reflections when the difference in successive elevations is greater than or equal to ¹/₈ of the incident wavelength
		4. Law of Plane Mirrors	D A combination of total internal reflection and dispersion is responsible for this phenomena. The critical ingredients are that the sun be behind your back and the rain falling in front of you.
		5. Law of Reflection	E when an electron captures the energy of an incident photon causing it to temporarily jump up into a higher orbital
		6. critical angle	F rays that spread apart from each other
		7. internal reflection	G. a number ³ 1 which represents the factor by which the speed of light in a vacuum is reduced when it travels through a transparent medium
		8. dispersion	H. an image which is "trapped" inside a mirror. It is formed by our eyes when we "dot back" the diverging rays that are reflected by a mirror.
		9. photon	I when light enters an more optically dense medium it bends in this direction
		10. bending towards the normal	J the bending of a wavefront when it enters a new medium because of a change in wave speed.
		11. diverging rays	K. d_i = -d_o
		12. virtual image	L the phenomena governing the usefulness of optical fibers
		13. rainbow	M a virtual image formed by the refraction of light waves over hot surfaces ... the heat gradient gradually alters air's index of refraction, causing the light wavefronts to bend.
		14. rough surface	N when light is emitted within an optically dense medium, and the angle of incidence equal or exceeds this value, the light is totally internally reflected back into the optically dense medium so that none of it escapes.
		15. index of refraction	O The breaking up of white light into its component colors when it passes through a transparent medium. Each color (frequency) has its own unique index of refraction, resulting in each color being slowed down to a slightly different degree. This is observed when the rays emerge out of the medium at slightly different angles. A spectrum.

Mirror Diagram

mirror #1 is on the left

P2 =

P21 =

Refraction Diagrams

Dcellreviewdiagramsmall.gif (2252 bytes) glassplatereviewdiagram.gif (2613 bytes)

1. Which ray represents the behavior of the light when it emerges from the water in the D-cell?

2. Which ray represents the behavior of the light when it enters the glass plate?

3. What is the average speed of light in the glass plate if the index of refraction is 1.6?

4. If the angle of incidence in the air in question #3 was measured to be 37º, what should be the angle of refraction in the glass? Where would these angles be measured with a protractor?

5. When the light emerges from the water in the D-cell, does its frequency or wavelength change?

6. Does refraction result in a fish appearing to be farther from or closer to the surface of a pond? How would you compensate to catch a fish with a spear versus a laser?

7. What is the minimum length of a plane mirror required for someone to see their entire body WITHOUT moving their head?

8. True or False? Diffuse reflections obey the law of reflection?

9. When white light passes through a triangular prism, which color is least deviated? That is, which frequency interacts the least with the electrons in the glass so that it is not slowed as much and emerges first?

10. True or False? Within an optical fiber, light travels in curved paths that match the curvature of the fiber.

11. True or False? A mirage is a reflection?

12. True or False? Atmospheric refraction makes our "days" shorter; that is, the number of hours of sunlight decreases because it must pass through ever thickening layers of the earth's atmosphere.