# Physics in Action

#### Refraction and Ray Optics

 Materials: Computer and School Network Time Allotment: 4 Class Days

### Overview:

If you have missed a portion of the Geometric Lens Optics Lab you have two options.

First, the scoring rubric for the lab included an adjustment for missing a portion of the lab. One option is to merely accept the grade which you received for the lab. Even though you may have missed one day out of five or six, you might still have a reasonable enough score to avoide doing a makeup lab.

Second, you could add some points to your lab score by completing the following Physics in Action piece. Each completed Physics in Action piece is equivalent to two missed days of point deductions. Thus, if you missed one or two days, then you would have to do one of these Physics in Action pieces. If you missed three or more days, then you will have to submit more than one of these Physics in Action pieces to completely make up for that which you have missed.

### The Assignment:

In Chapter 29 of the Hewitt Book (Regular and Conceptual Physics courses) and Chapters 24 and 25 of the Serway Book (Honors Physics and Chem-Phys courses), a variety of refraction phenomena are discussed. These phenomena (and others) were also discussed in class. Each refraction phenomenon involves the behavior of either a sound wave, a light wave, or some other type of wave upon crossing a boundary between two medium or while traveling through a non-uniform medium. Select one of the phenomena discussed in class or in the textbook and consider how it might be clearly and understandably explained to an eighth grader. Then write a short letter in which you do just that - explain a refraction phenomenon to an eighth grader. In your explanation, be sure to include the following:

1. identify the phenomenon which you will be explaining.
2. describe how the phenomenon involves the some principle of refraction.
3. explain the rule which governs the refraction of waves and apply the rule to explain the phenomenon which we observe.
4. include some form of an instructive, well-labeled diagram which complements your explanation.

To enhance the appearance of your letter, consider one of the following options:

• Use a word processor to write the letter.
• Construct the diagram using a graphics/draw program on the computer and electronically copy and paste it into the word processing document.

### Assessment:

Your writing assignment/makeup lab will be assessed using the following scoring rubric.

### 1.Physics Understanding

Demonstr'd understanding of wave refr'n by an accurate description and explan'n of a real-world phenomenon; utilized the vocab of physics to produce understandable ( to an eight grader) explan'ns; diagrams are a helpful complement to verbal explan'ns.

### 0 - 2

Understanding level is unsatisfactory as demonstrated by a description and explanation which is incorrect and faulty; the vocabulary of physics may have been misused or not even used at all

### 3 - 4

Made an effort to describe and explain a refraction phenomenon using the vocab of physics; explanations are satisfactory, yet lack in either detail, completeness, accuracy or vocabulary usage

### 5 - 6

Utilized physics vocab to produce an accurate description of a wave refraction phenomenon; explanations are insightful and complete; diagram is helpful and instructive; no major errors or omissions

### 2. Diagramming

Constructed a diagram which is relevant to the discussion and complements the explanations; used labels to clarify its meaning.

### 0

Failed to construct a diagram to accompany explanation

### 0.5 - 1

Diagram has limited usefulness due to lack of labels or relevancy to discussion

### 1.5 - 2

Diagram is instructive, well-labeled, and relevant to discussion

### 3. Writing Organiz'n

Involves a logical/sequential flow of ideas; utilized sufficient transitions; easy to follow thought process.

### 0

A good example of linguistic gymnastics

### 1

Only a few mistakes

Very Good