It's A Light, Bud, Author(s): David H. Bliss, Grade Level: 8th, Subject Area: Physical Science, - Look at a variety of light phenomenon and discuss with classmates possible causes/explanations for what has been observed: "mirage" mirror, holograms, "after image" from flash bulb (noting color of image), periscopes, rainbow from prisms, color from oil on water, et alius.

Planning Guide

Creating Learner-Focused
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* Madison-Oneida BOCES- This document may not be reproduced in any form without the expressed written consent of the District Superintendent or his designee.

LU Title: It’s a Light, Bud	Author(s): David H. Bliss
Grade Level: 8th	School Address: Mohawk Central School, 28 Grove Street, Mohawk, New York 13407
Subject Area: Physical Science	School Phone/Fax: 315-866-2620/315-867-2909

CONTENT KNOWLEDGE

Declarative	Procedural
speed of light in a vacuum and media	demonstrate the movement of sound and light in air and a vacuum
difference between light wave and sound wave	measure the speed of sound in air
reflection	calculate the speed of light in media
refraction	testing the law of reflection by measurement
absolute index of refraction	calculate the index of refraction
critical angle	measure the dispersion of light
electromagnetic spectrum wave nature of light lenses mirrors	measure/calculate wavelength using interference produce interference phenomenon demonstrate critical angle designing, constructing, describing apparatus for demonstrating light phenomena drawing lens/mirror diagrams

ESSENTIAL QUESTIONS

Why is the speed of light different in different media?
Why do we see colors in nature?
How would a scientist describe light?
How has the knowledge of light been used by man?
Which type of telescope is superior, a refracting telescope or a reflecting telescope?

INITIATING ACTIVITY

Look at a variety of light phenomenon and discuss with classmates possible causes/explanations for what has been observed: "mirage" mirror, holograms, "after image" from flash bulb (noting color of image), periscopes, rainbow from prisms, color from oil on water, et alius.

Connection to State Learning Standards

Content Area: Physical Science

Level: 8th

Benchmarks: Students will demonstrate an ability to answer questions posed in class and lab using investigative procedure including design, inquiry and analysis.

Benchmarks: Students will demonstrate an ability to record, analyze and present results of a science investigation through the use of computers and computer peripherals.

Standard: MST #1

Standard: MST #2

Unit Theme:

Light

Standard: MST #4

Standard: MST #3

Benchmarks: Students will demonstrate an ability to apply science concepts and equations to defend conclusions/predictions made during investigations.

Benchmarks: Students will demonstrate an ability to measure, record and analyze data using equations verified in lab experiences.

Learning Experiences

Declarative Knowledge

What declarative knowledge should e in the process of acquiring & integrating? As a result of the unit, the student will know or understand…

What experiences or activities will be used to help students acquire & integrate this knowledge?

What strategies will be used to help students construct meaning, organize and/or store the knowledge?

Describe what will be done.

*At Bottom

Various forms of Informal Lecture are used. A description of each type (noted below) is attached.

(1) Demonstration

(2) Responsive

(3) Guided

Note taking Group brainstorming for other examples of light and non-light EME

Students read textbook in applicable sections on topic, note taking

Students research Einstein for evidence of the importance of "c" as a constant and report

Students read text, not taking

Students read text, take notes

(see above)

Students read text, note taking

Demo frequencies of EM energy and methods of detecting each from radio thru x-ray

Practice using equation to solve for variables

Discuss the ramifications of "c" as the only constant in nature and time dilation and other relativistic phenomenon

Demonstrate change in direction of a light ray in different media and change in refraction angle with a change in color

Demo regular reflection and diffuse reflection using lasers

Demonstrate the refraction of light by water and glass and other transparent materials; show the reversibility of the path of the light as it passes from less dense to more dense and more dense to less dense media; calculate the speed changes in the light

Use Snell's Law equations to identify materials by their indices of refraction

Demo the critical angle for water; point out the use of the critical angle in communication using optical fiber

Demo dispersion by a prism and point out the dispersion that occurs in lens

Demonstrate the differential refraction of light from two colors of pins

Demonstrate the dispersion of light by water in an aquarium

Demonstrate the refraction of sound by CO2 in a balloon but the non-dispersive nature of the gas

Review by demonstration those phenomenon that are explained only by using the wave theory

Use ripple tank demo diffraction and interference of waves; use sound wave models to reinforce the model

Demo lasers; use the bugle model to explain the operation of lasers

Use the overlay models to demo the relationships in the double slit interference model

Demo polarization of light by filters, surfaces, crystals and the atmosphere

Use rope and slinky models to show the polarization of transverse but not longitudinal waves

Review the spectrum of the electromagnetic waves

Review the phenomenon we observe that depend on frequencies of EM energy being absorbed e.g. microwave ovens, blue skies, and x-rays

Discuss the size of the visible spectrum mathematically

*As a result of the unit, the student will know or understand…

1. Light is an electromagnetic disturbance that can create sensations of sight.

2. Speed of light and equation relating speed, wavelength and frequency.

3. The speed of light is an important physical constant (3 x 10 e8m/s).

4. The speed of light in a medium depends upon the frequency of light and the medium.

5. The incident ray, reflected ray and normal lie in the same plane.

6. The angle of incidence=the angle of reflection.

7. Regular reflection is produced by a polished surface; diffuse reflection is scattering of light caused by reflection from irregular surfaces.

8. Refraction is the change of direction that occurs when the light wave passes obliquely through a boundary across which there is a speed change and depends upon the nature of the medium.

9. When the wave enters a new medium obliquely, and there is a decrease in speed, the wave bends towards the normal (forms a smaller angle with the normal).

10. When the wave enters a new medium obliquely and there is an increase in speed, the wave bends away from the normal (forms a larger angle with the normal).

11. The absolute index of refraction is the ratio of the speed of light in a vacuum to the speed of light in a medium.

12. Snell's Law states that the ratio of the absolute indices of refraction is inversely proportional to: (1)the ratio of the line of the incident angle to the sine of the refractive angle (2)the ratio of the speed in the incident medium to the speed in the refractive material.

13. The critical angle is the angle of incidence for which the angle of refraction if 90 degrees; for light passing from a medium into air or a vacuum the sine of the critical angle equals the inverse of the index of refraction.

14. Total internal reflection occurs when the angle of incidence is greater than the critical angle.

15. Dispersion is the separation of polychromatic light into component wavelengths as light obliquely enters a dispersive medium.

16. Polychromatic light contains waves of different frequencies. Polychromatic light may be dispersed because each frequency has a different absolute index of refection.

17. A disperisve medium is a substance in which the speed of light depends on its frequency. Glass is a dispersive medium for light.

18. A non-dispersive medium is one in which the speed of light does not depend on the frequency. A vacuum is non-dispersive for light.

19. Much of the behavior of light can be interpreted in as wave phenomena.

20. Interference phenomenon can be produced by light and can be explained using the wave model.

21. Diffraction is the spreading of a wave into a region behind a barrier.

22. Coherent light sources are those producing waves with a constant phase relationship.

23. Double slit interference is produced by light from two coherent light sources according to the following relationship: wavelength divided by the slit separation equals the distance to the first oder interference times the distance to the screen.

24. Polarization is the separation of a beam of light so that the vibrations are in the same plane. transverse waves can be polarized; transverse waves cannot.

25. The electromagnetic spectrum contains radio waves, infrared waves, visible light waves, ultraviolet waves, x-ray waves, and gamma ray waves.

26. The different effects of electromagnetic waves on receivers is due to the difference in their frequencies.

27. Visible light is only a small portion of the EMS.

Learning Experiences

Procedural Knowledge

What procedural knowledge will students be in the process of acquiring & integrating? As a result of this unit, students will be able to:

What will be done to help students construct models, shape & internalize the knowledge?

Describe what will be done.

Demo movement of sound and light in air and a vacuum

Measure speed of sound in air

Calculate speed of light in a medium

Compare the speed of light and the speed of sound

Test law of reflection by measurement

Calculate the index of refraction for materials

Trace and compare the light ray path through various materials

Draw ray diagrams for light incident upon mirrors and lens

Use computer interface and probes for measurement

Use equations, measurement, calculations, computer interface/probes

Use equations, measurement, calculations

Discussion/comparison

Experiment, measurement, observation, diagram

Experiment, measurement, observation

Observing, measuring, drawing

Measuring, drawing, observing, classifying

Detect light in both vacuum and air; detect sound in air but not vacuum

Measure time and distance for sound to travel a measured distance; calculate the speed of sound/measurement of tube length to reinforce frequencies of sound

Use Snell's law to determine index of refraction for a medium; set equal to ratio of c/v for speed of light in a medium

Compare the measured speed of sound and light naming circumstances in nature when the differences can be observed

Use mirrors to trace the path of light rays to and from the surface of a plane mirror; draw the location of the virtual images formed of a drawn triangle

Shine laser light or other narrow beams of light through transparent materials and calculate the indices of refraction using the measured angles of incidence and refraction

Construct a diagram of a light ray as it passes at the same angle of incidence into several different materials

Construct diagrams for the path of light rays as they are reflected from objects positioned relative to the focal length of mirrors and lenses showing the position and size of the images formed

Learning Experiences

Extending and Refining

What knowledge will students be extending and refining? Specifically, they will be extending and refining their understanding of…

What reasoning process will they be using?

Describe what will be done.

Light waves

Reflection

Refraction

Diffraction

Interference

Electromagnetic Spectrum

Comparing

Classifying

Inductive Reasoning

Deductive Reasoning

Error Analysis

Analyzing Perspectives

Constructing Support

Abstracting

Other:

Throughout the year students will be given the opportunity to pursue a number of activities that will cause them to extend and refine their understanding of the topics listed to the left. It could include the following activities.

1. Constructing a reflecting telescope or a refracting telescope

2. Making a pinhole camera or using conventional camera to produce a photograph

3. Producing a holographic image

4. Constructing a "funhouse" using "plane" mirrors

5. Doing underwater photography

6. Attempt to build a Michelson-Morley apparatus for measuring the speed of light with some degree of accuracy

7. Construct a kaleidoscope

8. Produce a fiber optic system of communication using mono-filament fishline

9. Devise a method for determining the identity of "precious gems"

Planning Guide

Unit:

Step 1	Step 2	Step 3
*What knowledge* will students be using meaningfully? Specifically, they will be demonstrating their understanding of and ability to...........**	What reasoning process will they be using?	Describe student's products and performances and the criteria for evaluation.
	[ ] Decision Making (selecting from seemingly equal alternatives or examining the decisions of others) [ ] Problem Solving (seeking to achieve a goal by overcoming constraints or limiting conditions) [ ] Invention (creating something to meet a need or improve on a situation) [ ] Experimental Inquiry (generating an explanation for a phenomenon and testing the explanation) [ ] Investigation (resolving confusions or contradictions related to a historical event, a hypothetical past or future event, or to the defining characteristics of something) [ ] Systems Analysis (analyzing the parts of a system and how they interact) [ ] Other:	Products/Performances
		Criteria for evaluation

Rubric:

Key Questions:

What are the key elements, traits, or dimensions that will be evaluated?

Are the identified elements of equal importance or will they be weighed differently?

	Element #1	Element #2	Element #3	Element #4
Elements Scale	Product/Device Apparatus	Written Report	oral Presentation	Diagram of Device/Product
Weights	4	2	3	1
4	Design is clearly innovative/imaginative; operates effectively	Clearly and accurately gives a detailed account of device/project	Perfect diction, volume, eye contact, answers questions accurately	Clearly and accurately represents the product or device
3	Operates effectively but fails to show innovation in design	Summarizes the main points of the design/project	Good diction, volume, eye contact, answers contain some inaccuracies	Gives a clear representation of device but has some errors or omissions
2	Operates but erratically	Some details of the design/project are missing	Fair diction, volume, eye contact, answers questions hesitantly	Needs clarification and corrections
1	Design reasonable but is flawed; does not operate	Paper submitted but is missing may details of design/project	Poor diction, volume, eye contact, unable to answer questions	Diagram submitted but does not represent device well enough to be of value

NOTE: Rubric or other performance assessment instruments may be used.

Constructing a Holistic
Scoring Tool
(Rubric or Activity Specific Key)

Key Questions:

* How many score points are needed to discriminate among the full range of different degrees of understanding, proficiency, or quality?

This response, product, or performance provides evidence of understanding of concept/principle/generalization or proficiency in skill/process/strategy.

Score Point 4	Score Point 3
[ ]	[ ]
[ ]	[ ]
[ ]	[ ]
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Score Point 2	Score Point 1
[ ]	[ ]
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Have You Considered These Yet?

Learn to Learn Skills:

Peer tutoring

Assessment Modifications:

Peer assessment

Unit Schedule/Time Plan:

Four weeks

Written Overview:

This project is designed for 8th grade science students and requires approximately four weeks to complete. The unit should follow an introductory unit on waves. The unit incorporates technology with an interdisciplinary approach to learning. It should appeal to all levels of students since it is possible for students with a variety of learning skills to experience success.