lesson 5 what is static electricity? 5 what is static electricity? nagele, et al. 2016 page 51 ....
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LESSON 5 What is Static Electricity? Nagele, et al. 2016 page 50
LESSON 5 What is Static Electricity? Overview Students will learn about electricity as a form of energy, and explore
static electricity through experimentation. Student Learning Targets
I can define electricity and describe how electrons move within and between atoms to create electricity.
I can construct a model of an atom and explain the atoms particles and their charges.
I can explain static electricity and give an example of static electricity that I find in everyday life.
I can tell about lightning and how static electricity relates to how lightning works.
NGSS MS-PS1-1. Develop models to describe the atomic composition of simple
molecules and extended structures. [Clarification Statement: Emphasis is on developing models of molecules that vary in complexity. Examples of simple molecules could include ammonia and methanol. Examples of extended structures could include sodium chloride or diamonds. Examples of molecular-level models could include drawings, 3D ball and stick structures, or computer representations showing different molecules with different types of atoms.] [Assessment Boundary: Assessment does not include valence electrons and bonding energy, discussing the ionic nature of subunits of complex structures, or a complete description of all individual atoms in a complex molecule or extended structure is not required.]
Background Electricity is an integral part of everyday life that most people cant
imagine being without. Because most people take electricity for granted, few understand what it is or how it is generated. Electricity can be either static or current. When two objects come in close contact with each other (often through friction), one object can lose electrons to the other. Thus, one object becomes negatively charged because it gained electrons; while the other becomes positively charged because it lost electrons. Static electricity is the instantaneous movement of electrons due to this imbalance of states in which electrons move from negatively charged atoms towards positively charged atoms to restore balance. To
LESSON 5 What is Static Electricity? Nagele, et al. 2016 page 51
understand static electricity, students must grasp the following principles with regard to atoms and their charges:
Everything is Made of Atoms All things on earth are made up of elements. Each element on earth has a defined number of neutrons, protons, and electrons, making it unique. Individual particles of elements are called atoms. Atoms are the smallest piece of an element. Multiple atoms bonded together make molecules, and molecules bond together to make objects. Parts of an Atom Atoms are made up of positively charged protons, negatively charged electrons, and neutrons, which have no charge. The protons and neutrons are held tightly together in the nucleus or center of the atom. Negatively charged electrons orbit around the nucleus like planets orbit around the sun. The charge (strength) of one negatively charged electron is equal to the charge (strength) of one positively charged proton. When an atom has the same number of electrons and protons, the positive charges and negative charges are equal. This makes the overall atom neutral, or what scientist call balanced. Moving Electrons The neutrons and protons in an atom are held very tightly together in the atoms nucleus. However, electrons orbiting (moving in a path) around the nucleus are less tightly held, especially the further from the nucleus their orbit. Electrons far from the nucleus that are more loosely held can move from one atom to another. This movement of electrons generates electricity. Simply put, electricity is the movement of electrons. Some substances, like metals, lose electrons fairly easily. This property of metals makes them good conductors of electricity. Substances like glass, rubber, and wood hold on tightly to their electrons, making them poor conductors of electricity, and good insulators (opposite of conductor). Electrical Charges When an atom loses electrons, the electrons take their negative charges with them. Now the protons outnumber the electrons giving the atom an overall positive charge. When an atom gains electrons, the electrons outnumber the protons, giving the atom an overall negative charge. Because atoms make up molecules, which in turn make up objects; molecules and objects can have an overall positive or negative charge because of the charge of their atoms.
LESSON 5 What is Static Electricity? Nagele, et al. 2016 page 52
When two objects of opposite charges come in contact with each other they attract each other (like the north and south poles of two magnets). When two objects of the same charge (whether both are positive or negative) come in contact, they repel each other. This repelling action is similar to that of magnets when like poles repel.
Static Electricity Electricity can be generated in a couple of ways by moving electrons from one place to another. How this movement occurs determines whether static or current electricity is produced as a result. With static electricity, electron movement is instantaneously. Whereas, in current electricity electrons move continuously along a pathway called a circuit. Lightning, static cling, and static shocks are all examples of static electricity. Static electricity is generated when two differently charged objects come in contact with each other (usually through friction) causing the instantaneous movement of electrons. The electrons move from the negatively charged object to the positively charged objects restoring balance of both to neutral. A charged object will also attract an object that is neutral. Through friction, an insulating material such as a rubber balloon will take on an overall negative charge. This happens when you rub the balloon on your hair or wool because the balloon picks up electrons from the hair or wool on that side of the balloon. If you hold the side of the balloon charged with the extra electrons next to a neutral object like wood, it will stick. This is because the negative side of the balloon repels the electrons in the surface of the wood, causing the electrons to shift to the far side of their orbits. In doing so, the atoms nucleus containing the positively charged protons is closer to the wood surface. The opposite charges of the balloon and wood surface attract each other. This attraction lasts for a
opposite charges attract
like charges repel
LESSON 5 What is Static Electricity? Nagele, et al. 2016 page 53
very short period of time. The extra electrons in the balloon leak off, and both the balloon and surface of the wood return to their natural neutral states.
Adapted from http://www.teachengineering.org/ See handout Fundamentals of Electricity which can be shared with students.
Vocabulary Electricity, proton, electron, neutron, charge, static electricity, current
electricity, conductors, circuits, negatively charged, positively charged, elements
Resources Static Electricity http://www.sciencemadesimple.com/static.html Static Electricity 4 http://sciencenetlinks.com/lessons/static-electricity-
4/ Activity: Charge It Free resources for K-12: www.teachengineering.org
NDT Resource Center an easy to understand website on electricity that explains what electricity is, using atom models. Animated: http://www.ndted.org/EducationResources/HighSchool/Electricity/elements.htm.
Energy Story another good website that explores energy and electricity: http://energyquest.ca.gov/story/chapter02.html.
LESSON 5 What is Static Electricity? Nagele, et al. 2016 page 54
Materials For each student 1 pencil 1 science notebook 1 paper towel 3 colored pencils of different colors 1 small bag of M&Ms Renewable & Nonrenewable worksheet
For each table group 2 colored pencils of each color: orange, brown, red, yellow, blue,
green 2 magnets
For the class Overhead transparencies of helium and copper atoms Overhead 2 Atom Overhead 6 Static Electricity: Charged Atoms Overhead 7 Static Electricity: Investigation Six balloons, inflated up to a circumference of about 15 inches Three pieces of wool or fleece cloth, each piece about 2 x 2 or larger Access to a faucet with a steady stream of water, a table and a wall Six packets of unflavored gelatin; place dry contents of two packages
onto each of three paper plates One copy for each activity station of Static Electricity: Investigation
Preparation Gather together supplies, and set up static experiment stations. Time 60 minutes Procedure 1. Prior to starting a new topic have students review the previous lesson
by individually completing the Renewable & Nonrenewable worksheet (Overhead 1).
2. Tell students that during this lesson they will have a chance to share
what they know about the form of energy called electricity. Tell them that they are going to begin with a brainstorming activity in which each student will take turns sharing what they already have learned or know. Ask students to raise their hands to share their ideas. OR,