During this CELL, students will conduct several investigations focused on basic concepts of electricity. Through experimentation and observation, students will explore static electricity and electrical current.
Through various activities and investigations, students will find that the surfaces of objects can have a positive charge, negative charge, or be neutral based on the charged particles on the surface of the object. When an object has a positive or negative charge, it is attracted to materials or surfaces that are neutral or oppositely charged. In contrast, two objects having the same charge repel one another.
This CELL gives students the opportunity to examine electrical current by creating circuits. Students first create simple circuits, discovering that to observe a complete circuit, the following are needed: a power source, a path for the electrical current to follow, and an indication that electrical current is flowing. Throughout students’ exploration, they will use a battery as a power source, wires through which current can flow, and a light bulb which lights to indicate that the circuit is complete and that electricity is flowing.
Certain materials are able to carry electrical current more easily than others. Students will test various objects and will conclude that materials such as wood, rubber, plastic and glass are poor conductors of electrical current, while others such as metal are better able to conduct electrical current.
Through exploration, students will find that different types of circuits carry electrical current. Students will discover that simple circuits consist of one power source, one bulb, and wires. In addition, students will create series circuits and parallel circuits by using one power source and multiple bulbs arranged in series (one path through which electrical current flows) and parallel (multiple paths through which electrical current flows).
This CELL will broaden students’ knowledge of static electricity and electrical current, enabling them to have a greater understanding of and appreciation for the vast world of electricity which surrounds them. This greater understanding will better enable students to safety utilize the electricity which fuels their everyday lives.
___________________________________________________________________
Investigation 1: Discovering Static Electricity
In Investigation 1, students will begin their study of electricity by exploring static electricity. Students will create charged surfaces by rubbing balloons with wool. By doing this, students will discover that as the number of times a balloon is rubbed increases, the likelihood that the balloon will stick to a piece of paper on the wall also increases.
Investigation 1: Teacher’s Video (4:17)
Investigation 1: Student’s Video (8:24)
___________________________________________________________________
Investigation 2: Observing Electrical Charge
Students will continue their exploration of static electricity in Investigation Two. Students will compare the response of materials to uncharged and charged wool swatches and balloons. Students will hold the uncharged and charged wool swatches and balloons over a plate of salt and pepper and over their arms. Students will observe the attraction between the charged materials and the neutral salt and pepper and their neutral arms. Finally, students will hold a charged balloon near another charged balloon suspended on a string. Observing the suspended balloon move away from the balloon being held, students will determine that objects with like charges repel one another.
Investigation 2: Teacher’s Video (2:49)
Investigation 2: Student’s Video (10:01)
___________________________________________________________________
Investigation 3: Understanding Simple Circuits
Investigation Three introduces students to the concept of current electricity and provides them with the opportunity to construct a simple circuit with a battery, a wire, and a light bulb. Students will also follow five illustrations and test five different constructions to determine which is a complete circuit.
Investigation 3: Teacher’s Video (3:28)
Investigation 3: Student’s Video (5:32)
___________________________________________________________________
Investigation 4: Examining Electrical Properties
In Investigation Four, students will test the ability of various substances to conduct electricity. By exploring these materials, students discover that wood, rubber, plastic and glass are poor conductors of electrical current, while metal is a good conductor. Students will also find that some objects, such as pencils, contain materials that are conductors of electrical current as well as materials that are insulators and do not conduct electrical current.
Investigation 4: Teacher’s Video (3:22)
Investigation 4: Student’s Video (8:33)
___________________________________________________________________
Investigation 5: Exploring Series and Parallel Circuits
Students continue their exploration of electricity in Investigation Five. This investigation introduces students to series and parallel circuits through a series of experiments. Students will construct a series circuit and a parallel circuit and will compare the amount of light coming from the bulbs in each circuit. In addition, students will remove a bulb from each circuit and will note whether or not the circuit remains complete. Through testing and making observations, students will learn the distinguishing properties of each type of circuit.
Investigation 5: Teacher’s Video (4:44)
Investigation 5: Student’s Video (8:29)
___________________________________________________________________
Investigation 6: Performance Assessment
Investigation 6 Six consists of a performance assessment designed to evaluate students’ understand of the science concepts addressed in the first five investigations of the CELL. During this exploration, students will design and construct electrical circuits in a model house, demonstrating understanding of simple, parallel, and series circuits.
Investigation 6: Performance Assessment – Teachers Only (2:15)