2. Electricity: A Mysterious Force By: Mrs. Hennigan Minot Forest Elementary School

3. Atoms Building blocks of the universe Building blocks of the universe Millions would fit on the head of a pin! Millions would fit on the head of a pin! Made up of particles: Made up of particles: 1. Protons (+) 2. Neutrons (no charge) 3. Electrons (-) spin around the nucleus (center of the atom)

4. Opposites Attract Protons (+) and Electrons (-) are attracted to each other Protons (+) and Electrons (-) are attracted to each other They carry an electrical charge They carry an electrical charge Electrical force keeps the electrons in their shells, or orbits Electrical force keeps the electrons in their shells, or orbits Electricity: moving electrons Electricity: moving electrons

5. How are magnets like protons and neutrons?

6. Elements When all the atoms of a substance are the same they are called elements When all the atoms of a substance are the same they are called elements Example: all the atoms of oxygen are the same Example: all the atoms of oxygen are the same The number of protons determines the element The number of protons determines the element Oxygen’s atomic number is 8 Oxygen’s atomic number is 8 Hydrogen’s atomic number is 1 Hydrogen’s atomic number is 1 What molecule is this? What molecule is this?

7. Static Electricity Electrons are forced to move from one atom to another Electrons are forced to move from one atom to another You can rub electrons off a balloon You can rub electrons off a balloon The electrons move into your hair! The electrons move into your hair! Shocking! Shocking! Bad Hair Day! Bad Hair Day!

8. Lightning A form of electricity A form of electricity Electrons move from Electrons move from one cloud to another or jump from a cloud to the ground one cloud to another or jump from a cloud to the ground

9. Batteries 2 different metals in a chemical solution 2 different metals in a chemical solution Chemical reaction causes electrons to move Chemical reaction causes electrons to move Each end of the battery connects to a metal Each end of the battery connects to a metal Positive charged end: releases more electrons Positive charged end: releases more electrons Negative charged end: releases less electrons Negative charged end: releases less electrons Strength of a battery- measured in volts Strength of a battery- measured in volts

10. Electricity Travels in Circuits Current is the flow of electricity in a path, or circuit Current is the flow of electricity in a path, or circuit Open circuit: no flow Open circuit: no flow Closed circuit: flow Closed circuit: flow Electricity flows through wire and lights the bulb Electricity flows through wire and lights the bulb How can you open and close a circuit in our classroom? How can you open and close a circuit in our classroom? A switch opens and closes a circuit.

11. Series and Parallel Circuits Bulbs connected in series have only one path for the current Bulbs connected in series have only one path for the current Bulbs connected in parallel have two paths for the current Bulbs connected in parallel have two paths for the current Are your Christmas tree lights connected in a series or parallel circuit? Are your Christmas tree lights connected in a series or parallel circuit? Series Series Series circuit Parallel circuit

12. Schematics of Circuits Series Circuit Parallel Circuit

13. What are: Solid Conductors? Conductors: any object that allows electrical current to flow though it. Conductors: any object that allows electrical current to flow though it. Wire is the most common conductor in a circuit Wire is the most common conductor in a circuit Non-conductors: do not allow electrical current to flow. Non-conductors: do not allow electrical current to flow. http://www.bbc.co.uk/schools/ks2bitesize/science/activities/circuits_conductors.swf

14. Liquid Conductors Which liquids conduct electricity? Which liquids conduct electricity? Which liquids are the best conductors? Which liquids are the best conductors? Which solution is a non-conductor? Which solution is a non-conductor? 1. Water 2. Water and salt solution 3. Water and sugar solution 4. Water and baking soda solution

15. Resistance to the flow Would the same amount of water forced through pipes move slower in a larger pipe or a smaller pipe? Would the same amount of water forced through pipes move slower in a larger pipe or a smaller pipe?

16. Electrical Resistance Resistance: when the flow of electrons is slowed down Resistance: when the flow of electrons is slowed down Different metals have different resistance Different metals have different resistance Which has the least resistance ? Which has the least resistance ? 1. Copper 2. Aluminum 3. silver Which has more resistance-thick or thin wire? Which has more resistance-thick or thin wire? Which has more resistance- longer or shorter lengths of wire? Which has more resistance- longer or shorter lengths of wire?

17. Fuses When electrons meet under resistance, this causes friction with the matter (conductor). When electrons meet under resistance, this causes friction with the matter (conductor). This friction causes heat. This friction causes heat. If there is too much heat, the conductor melts. If there is too much heat, the conductor melts. Fuses are a device that has a wire inside them that melts and breaks if there is too much heat. Fuses are a device that has a wire inside them that melts and breaks if there is too much heat. This stops the flow of electricity and prevents fire! This stops the flow of electricity and prevents fire!

18. Parts of a Light Bulb Filament: coiled wire that heat up but does not melt Filament: coiled wire that heat up but does not melt Support wires: hold the filament in place Support wires: hold the filament in place Insulator (non-conductor): prevents overheating Insulator (non-conductor): prevents overheating Gas: helps keep the filament from evaporating Gas: helps keep the filament from evaporating Glass bead: separates the wires Glass bead: separates the wires

19. Review the Vocabulary Volt Volt Battery Battery Series circuit Series circuit Parallel circuit Parallel circuit Current Current Switch Switch Resistance Resistance ELECTRICITY ELECTRICITY Insulator Insulator Conductor Conductor Circuit Circuit Atom Atom Electron Electron Proton Proton Neutron Neutron Nucleus Nucleus Home