Polarized Light

LabPaq® is a registered trademark of Hands-On Labs, Inc. (HOL). The LabPaq referenced in this manual is produced by Hands-On Labs, Inc. which holds and reserves all copyrights on the intellectual properties associated with the LabPaq’s unique design, assembly, and learning experiences. The laboratory manual included with a LabPaq is intended for the sole use by that LabPaq’s original purchaser and may not be reused without a LabPaq or by others without the specific written consent of HOL. No portion of any LabPaq manual’s materials may be reproduced, transmitted or distributed to others in any manner, nor may they be downloaded to any public or privately shared systems or servers without the express written consent of HOL. No changes may be made in any LabPaq materials without the express written consent of HOL. HOL has invested years of research and development into these materials, reserves all rights related to them, and retains the right to impose substantial penalties for any misuse.

Published by: Hands-On Labs, Inc.

3880 S. Windermere St. Englewood, CO 80110 Phone: 303-679-6252 Toll-free: 1-866-206-0773 Fax: 270-738-0979

www.LabPaq.com

E-mail: [email protected]

Printed and bound in the United States of America.

ISBN: 978-1-866151-40-6

The experiments in this manual have been and may be conducted in a regular formal laboratory or classroom setting with the user providing their own equipment and supplies. The manual was especially written, however, for the benefit of independent study students who do not have convenient access to such facilities. It allows them to perform physics experiments at home or elsewhere by using LabPaq PK-2, a collection of experimental equipment and supplies specifically packaged by Hands-On Labs, Inc. to accompany this manual.

Use of this manual and authorization to perform any of its experiments are expressly conditioned upon the user reading, understanding, and agreeing to abide by all the safety precautions contained herein. Although the author and publisher have exhaustively researched all sources to ensure the accuracy and completeness of the information contained in this book, we assume no responsibility for errors, inaccuracies, omissions or any other inconsistency herein. Any slight of people, organizations, materials or products is unintentional.

Table of Contents Introduction …………………………………………………………………………………………………………………. 4

Important Information to Help Students Study Science …………………………………………….. 4 WELCOME TO THE WORLD OF SCIENCE! …………………………………………………………………….. 4

Laboratory Equipment and Techniques ………………………………………………………………… 13 Use, Disposal, and Cleaning Instructions for Common Materials …………………………….. 19

HOW TO WRITE LAB NOTES AND LAB REPORTS ………………………………………………………… 21 Lab Notes ………………………………………………………………………………………………………….. 21 Lab Reports ……………………………………………………………………………………………………….. 23 Laboratory Drawings …………………………………………………………………………………………… 27 Visual Presentation of Data …………………………………………………………………………………. 28 Computer Graphing Using MS Excel ……………………………………………………………………… 32

SAFETY CONCERNS ………………………………………………………………………………………………… 40 Basic Safety Guidelines ………………………………………………………………………………………. 41 Material Safety Data Sheets ………………………………………………………………………………… 46 Science Lab Safety Reinforcement Agreement ……………………………………………………… 50

EXPERIMENTS 1. Static Electricity or Electrostatics ………………………………………………………………………… 53 2. Electric Fields ……………………………………………………………………………………………………. 63 3. Introduction to Electrical Circuits ………………………………………………………………………… 74 4. Resistors in Series and Parallel ………………………………………………………………………….. 87 5. Semiconductor Temperature Sensor …………………………………………………………………… 96 6. Capacitance in a Circuit ……………………………………………………………………………………. 102 7. Electric Motor ………………………………………………………………………………………………….. 113 8. Reflection and Refraction …………………………………………………………………………………. 119 9. Diffraction Grating …………………………………………………………………………………………… 130 10.Polarized Light ………………………………………………………………………………………………… 141 11.Radioactive Decay …………………………………………………………………………………………… 147 APPENDIX Using Statistics …………………………………………………………………………………………………….. 154

© Hands-On Labs, Inc. LabPaq PK-2 4

Introduction Important Information to Help Students Study Science

Version 09.3.05

WELCOME TO THE WORLD OF SCIENCE! Don’t be afraid to take science courses. When you complete them, you will be very proud of yourself and will wonder why you were ever afraid of the “S” word – Science! After their first science course most students say they thoroughly enjoyed it, learned a lot of useful information relevant to their personal lives and careers, and only regret not having studied science sooner. Science is not some mystery subject comprehended only by eggheads. Science is simply a way of learning about our natural world and how it works by testing ideas and making observations. Learning about the characteristics of the natural world, how those characteristics change, and how those characteristics interact with each other make it easier to understand ourselves and our physical environment and to make the multitude of personal and global decisions that affect our lives and our planet. Plus, science credits on an academic transcript are impressive, and your science knowledge may create some unique job opportunities. All sciences revolve around the study of natural phenomena and require hands-on physical laboratory experiences to permit and encourage personal observations, discovery, creativity, and genuine learning. As increasing numbers of students embrace online and independent study courses, laboratory experiences must remain an integral part of science education. This lab manual’s author and publisher are science educators who welcome electronic technology as an effective tool to expand and enhance instruction. However, technology can neither duplicate nor replace learning experiences afforded to students through traditional hands-on laboratory and field activities. This does not mean that some experiments cannot or should not be replaced or reinforced by computer simulations; but any course of science study must also provide sufficient hands-on laboratory and field experiences to:

Engage students in open-ended, investigative processes by using scientific problem solving.

Provide application of concepts students have seen in their study materials which

reinforce and clarify scientific principles and concepts.

Involve multiple senses in three-dimensional rather than two-dimensional learning experiences that are important for greater retention of concepts and for accommodation of different leaning styles.

© Hands-On Labs, Inc. LabPaq PK-2 5

Stimulate students to understand the nature of science including its unpredictability

and complexity.

Provide opportunities to engage in collaborative work and to model scientific attitudes and behavior.

Develop mastery of techniques and skills needed for potential science, engineering, and technology careers.

Ensure advanced placement science courses transfer to college credit.

The knowledge gained from science courses with strong laboratory components enables students to understand in practical and concrete ways their own physical makeup, the functioning of the natural world around them, and contemporary scientific and environmental issues. It is only by maintaining hands-on laboratory experiences in our curricula that the brightest and most promising students will be stimulated to learn scientific concepts and avoid being turned-off by lecture- and textbook-only approaches. Physical experimentation may offer some students their only opportunity to experience a science laboratory environment. All students – as potential voters, parents, teachers, leaders, and informed citizens – will benefit from a well-rounded education that includes science laboratory experiences, when it is time for them to make sound decisions affecting the future of their country and the world. 19th century scientist, Ira Remsen (1846-1927) on the subject of Experimentation: