# Electricity and Circuits

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Electricity and Circuits
Lesson 28 Part I The slide show consists of 4 parts. The first part is provided to help work in some background materials and vocabulary dealing with electricity. It provides a few activities that involve the students in helping demonstrate some of the concepts listed previously. The activities and introduction lead into the second part of hands-on lab stations. The third part emphasizes cost and safety. Finally, the fourth part introduces solar power and more hands on materials. Not every school can afford to buy all of the resources listed, but the list is provided in order for the teacher to pick one or two to help in teaching these concepts from year to year.

GPS S8P5. Students will recognize characteristics of gravity, electricity, and magnetism as major kinds of forces acting in nature. b. Demonstrate the advantages and disadvantages of series and parallel circuits and how they transfer energy.

What is Electricity? Electricity is generated from the motion of tiny charged atomic particles called electrons and protons! Protons = + Electrons = - Electricity This slide introduces electricity at the smallest scale possible. The idea that things are charged should be emphasized over and over. It is good to mention static electricity. That is, shocking someone with electricity is simply the movement of these positive and negative charges. As a presenter of this material, I find it good to have the students repeat the words proton and electron, telling me whether it is positively charged or negatively charged. By doing it this way, I can say positive and negative charge throughout the rest of the presentation. It is not intended for the students to understand the principle parts of matter nor understand concepts related to the nucleus and creation of charge. Nucleus Energy Levels

What is Electricity? Electrons orbit the nucleus of an atom at different distances often referred to as levels. Each “energy level” contains a particular number of electrons at its maximum. Electrons in different energy levels can jump from one atom to another. These jumps change the overall charge of the atoms. The changes result in electricity. Electricity This slide introduces electricity at the smallest scale possible. The idea that things are charged should be emphasized over and over. It is good to mention static electricity. That is, shocking someone with electricity is simply the movement of these positive and negative charges. As a presenter of this material, I find it good to have the students repeat the words proton and electron, telling me whether it is positively charged or negatively charged. By doing it this way, I can say positive and negative charge throughout the rest of the presentation. It is not intended for the students to understand the principle parts of matter nor understand concepts related to the nucleus and creation of charge. Nucleus Energy Levels

Electric Current Electric current is the flow of electric charges.
Electric current is measured in amperes (A), of amps. Electric charges will always flow from a region of higher potential energy to a region of lower potential energy. Electric Vocabulary I use this slide to briefly give a definition of each of these terms, having the students repeat the words. I emphasize that a circuit requires a source (energy) and a load to power such as a lamp or light bulb. After explaining the basics parts of the circuit, describe to them that a power outage is a break in the circuit. A circuit has to be a connected loop for electricity to get where it is supposed to go. A transformer helps “transform” the electricity to a form (steps it down) that powers the things in your house. Without transformers, the electricity coming into our homes would break our appliances and TV’s(too much electricity). With insulator and conductor, it is easy to tell them that one allows electricity to flow through it (conductor) while the other does not (insulator). With proton and electron, I ask them the charge--positive or negative-- as explained earlier.

Electric Current Even though the current, voltage, and resistance vary from circuit to circuit, there is often a simple relationship among them. This relationship is Ohm’s law. Ohm’s law states that the current (I) in a wire is equal to the voltage (V) divided by the resistance (R). Current (I) = Voltage (V)/Resistance (R)

Electric Current The difference in potential energy between two locations is know as potential difference. Potential difference results from differences in the electrical charge in two locations. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Electric Current Potential difference is called voltage and is measured in units called volts (V). A battery is a device that converts chemical energy into electricity. In batteries the potential energy difference is created by the positive and negative terminals. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits A circuit is a path through which electricity can flow.
Charges will flow in a circuit when there is potential difference. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits A circuit may also have a switch that can be open, which stops the flow of current, or closed, which allows current to flow. Energy flows only through a circuit that is closed. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits Energy Source
A circuit needs an energy source to push a charge through the circuit A battery creates a potential difference between its negative and positive terminals Electric charges are repelled by negative terminal and attracted toward the positive terminal. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits Loads A load is a device in a circuit that operates using electrical energy. Examples of loads are light bulbs, bells, radios, and motors. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits Conductors A conductor is a material that allows electrical energy to flow through it easily. Metals make good conductors, so wires from metals are most often the conductors in circuit. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits Resistors A resistor is an object added to a circuit that restricts the flow of electrical energy. Resistors inhibit the flow of electric current by producing a voltage drop when current passes though them. Resistors can be used to produce a desired potential difference They limit current and cause some electric energy to be give off as heat. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Circuits Switch A switch is a device that is used to control the flow of current through a circuit. A switch works by separating (open) or bringing together (closed) two conductors attached to the circuit. When a switch is open, the path is broken, so not electricity flows through the circuit When a switch is closed, it creates a continuous path through which an electric charge can flow. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Series Circuits A series circuit is a circuit that provides only one possible path for the flow of current. In a series circuit, the loads are set up in a series, or line, that requires current to flow through one load before passing through the next. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Parallel Circuits A parallel circuit offers more than one path for the flow of electricity. Each load in a parallel circuit has its own closed circuit pathway to the energy source. Loads in a parallel circuit uses the full voltage of the energy source. No Electricity Electricity is beneficial to us all the time. This slide helps put a realistic perspective on how much electricity plays a role in our everyday life. Asking a few simple questions helps the students think about how their lives would be affected without electricity.

Electricity and Magnetism
Lesson 29 Part II The second part of this slide show presents a few of the hands-on lab stations that should be setup around the classroom for the students to experiment with electricity. The slides cover the materials needed, a diagram of the setup, and the directions for each activity. For 2nd graders, a teacher or volunteer needs to be with the kids at each of the four stations. All of these stations helped keep the students active and participating while I presented the material. These slides are to be used as a reference for the teacher or shown as a wrap up or review of the activities for the students.

GPS S8P5. Students will recognize characteristics of gravity, electricity, and magnetism as major kinds of forces acting in nature. c. Investigate and explain that electric currents and magnets can exert force on each other.

Magnets Magnetic force is a push or pull that is exerted by a magnet.
A magnet has two poles North & South Magnets In Part I, the idea of positive and negative charges was introduced. Since magnets have a positive and a negative charge, they are very useful tools in illustrating charge (because they can push or pull other things as well as each other). They also teach the students about things they cannot see. You cannot see the magnetic field, but when the magnets repel or attract each other, you know that some type of charge or magnetic field is present.

Magnets Poles that are alike repel or push apart
Poles that are unalike attract or pull together Magnets In Part I, the idea of positive and negative charges was introduced. Since magnets have a positive and a negative charge, they are very useful tools in illustrating charge (because they can push or pull other things as well as each other). They also teach the students about things they cannot see. You cannot see the magnetic field, but when the magnets repel or attract each other, you know that some type of charge or magnetic field is present.

Magnets The area surrounding a magnet in which the magnetic force exists is called the magnetic field. Magnets In Part I, the idea of positive and negative charges was introduced. Since magnets have a positive and a negative charge, they are very useful tools in illustrating charge (because they can push or pull other things as well as each other). They also teach the students about things they cannot see. You cannot see the magnetic field, but when the magnets repel or attract each other, you know that some type of charge or magnetic field is present.

Magnets In the 1800’s, a Danish scientist named Hans Oersted discovered that passing a current through a piece of wire caused a magnetic field to form around the wire. The production of a magnetic field by electric current is called electromagnetism. Magnets In Part I, the idea of positive and negative charges was introduced. Since magnets have a positive and a negative charge, they are very useful tools in illustrating charge (because they can push or pull other things as well as each other). They also teach the students about things they cannot see. You cannot see the magnetic field, but when the magnets repel or attract each other, you know that some type of charge or magnetic field is present.

Magnets A magnet that is made by passing an electric current through a coil of wire wrapped around an iron core is called an electromagnet. Magnets In Part I, the idea of positive and negative charges was introduced. Since magnets have a positive and a negative charge, they are very useful tools in illustrating charge (because they can push or pull other things as well as each other). They also teach the students about things they cannot see. You cannot see the magnetic field, but when the magnets repel or attract each other, you know that some type of charge or magnetic field is present.

Magnets An electromagnet consists of an iron core placed inside a wire coil. The magnetic field strength of a wire coil carrying an electric current increases in direct proportion to the number of turns of the coil. Magnets In Part I, the idea of positive and negative charges was introduced. Since magnets have a positive and a negative charge, they are very useful tools in illustrating charge (because they can push or pull other things as well as each other). They also teach the students about things they cannot see. You cannot see the magnetic field, but when the magnets repel or attract each other, you know that some type of charge or magnetic field is present.

Uses of Electromagnets
Changing the Strength of an Electromagnet To Increase Strength To Decrease Strength Increase strength of current Decrease strength of current Add more coils of wire Use fewer coils of wire Increase size of iron core Decrease size of iron core

Uses of Electromagnets
An electric motor is a device that transforms electrical energy into mechanical energy. Washers and dryers are two appliances that operate using motors.

Uses of Electromagnets
A generator is a device that transforms mechanical energy into electrical energy. The electrical systems of many cars use electricity produced by generators to work.

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