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Teacher Notes Topic: Static Electricity National Science Standards Addressed: CONTENT STANDARD
B: As a result of their activities in grades 9-12, all students should develop
an understanding of Missouri Standards Addressed MO Standard Strand 1.2A: *Forms of energy have a source, a means of transfer (work and heat), and a receiver. *Describe the interactions (i.e., repel, attract) of like and unlike charges (i.e., magnetic, static electric, electrical) Objectives: Students will be able to 1. Discuss how charges are created. 2. Charge an object and demonstrate the presence of charges on a body. Concept Addressed This lesson is an introductory lesson to static electricity - electricity that is not in motion. Matter is made up of electrons ( negatively charged particle) and protons which have positive charge on it. Atoms are usually neutral but under certain conditions they become unbalanced in their electrical charge, When this happens, we say that an object is charged. When an object that is positively charged comes close to a negatively charged object, they attract and if they get in contact, you may see electrical spark. When this happens we say that an electrical discharge has occurred. When charges on two objects are the same, they repel each other. Activities To Teach Concept: Activity 1: This activity involves the use of pepper and salt. A pile of pepper and salt will be in a plate. Students will be asked to place a plastic ruler over a pile of pepper and record their observation. They are then asked to rub the ruler on their head or rub the given cloth over it and place over the salt and pepper again and record what happens this time. Activity 2: Ask students to try to stick a balloon on a wall, then rub the balloon with some cloth and stick on the wall again and record what happens. Activity 3: Students will then be asked to try both activities again using a piece of wood, and record what happens. Data to Be Collected Students will record their observations in the above situations in their journals. See Student Sheet Explanation Phase: Now is the time to introduce facts about static electricity. Students are to report to the class their findings at this time and possible reasons why the materials behaved the way they did. Through questions and answers beginning at the students' lab results, teacher introduces electrons as very small particles that are negatively charged. Some materials are also prone to to loosing electrons faster than others. Such substances are called insulators, and some that cannot be charged up like copper are called conductors. Discuss various degrees of electron-binding. Use diagrams to explain how excess electrons are created on the surface of the balloon when rubbed against their hair, these electrons "jump" at the wall so to speak when the balloon is brought near the wall. We say that there is an attraction between the wall and the balloon. You may need to introduce the properties of some materials, like fur, to easily create static electricity. Discuss how factors like dry surrounding enhance production of static electricity, for instance in the winter. Application Phase: In this phase students will apply their newly learned concept to work. Provide students with little pieces of paper. Their mission is to get the plastic ruler and the balloon to pick up these tiny pieces of paper. Students should report what they did and the result of it in their journal. This phase requires students to apply their newly learned concept in another situation. Materials List. 1.Balloons(30) 2.Salt 3.Pepper 4.Cloth 5. Plastic Rulers(12) 6. Paper plates 7. Pieces of paper. Historical Background: Later, other experimenters discovered that other substances, such as diamonds, also attracted light objects the same way amber did. These substances are called insulators. They also discovered that other substances, such as copper, silver, and gold, did not attract anything, no matter how long the object was rubbed and no matter how light or heavy the other object was. These are called conductors because they let electricity flow through them. References: Douglas Llewellyn (2003) Inquire Within, Implementing Inquiry-based Science Standards |