ELECTROMAGNETISM

1. ELECTROMAGNETISM

2. Bell Work Welcome back, I hope you had a great break! (Write each statement then decide if it is true or false, if false correct) • The basic particles of an atom are protons, neutrons, and nuclei. • Particles that make up an atom have no charge. • Electrons are negatively charged.

3. Unlike charges attract. Like charges repel. Electricity 1.1 Vocab • Electric charge – a property that allows an object to exert an electric force on another object without touching it.

4. 1.1 Vocab Cont. • Electric field – the space around a particle through which an electric charge can exert force

5. At first, a balloon and a glass rod each have balanced, neutral charges. 1.1 Vocab Cont. • Static charge – a buildup of electric charge in an object caused by the presence of many particles with the same charge

6. Afterwards, the balloon has a negative charge, and the rod has a positive charge. At first, a balloon and a glass rod each have balanced, neutral charges. When they touch, electrons move from the rod to the balloon.

7. 1.1 Vocab Cont. • Induction – the buildup of a charge without direct contact

8. Bell Work Draw a picture and explain each answer. 1. How do two positive particles interact? 2. How do two negative particles interact? 3. How do a positive and a negative particle interact?

9. Bell Work Please answer the following questions using complete sentences. • A sock and a shirt from the dryer stick together. What does this tell you about the charges on the sock and shirt? 2. You walk over a rug and get a shock from a doorknob. What do the materials of the rug and the shoes have to do with the type of charge your body had?

10. AssignmentRead pg 18- 25 then… Choose one of the following to complete • Make a PowerPoint for the vocab words on page 18. Each word should have 2 slides. First slide: word, definition, and a sentence in your own words. Second slide: word and a picture. • Make a 4 square chart  For each of the vocab words on page 18.

11. 1.2 Vocab Electric potential – the amount of electric potential energy per unit charge at a certain position in an electric field. Volt – equal to one joule of energy per coulomb of charge

12. Conductor – a material that allows an electric charge to pass through it easily Insulator – a material that does not easily allow a charge to pass through it.

13. Resistance – the property of a material that determines how easily a charge can move through it Ohms – the unit for measuring electrical resistance

14. Grounding – providing a harmless, low-resistance path (a ground) for electricity to follow

15. Bell Work 5/12/11 Draw a picture and explain what happens when there is lightning. (hint look at pg 25)

16. Bell Work 5/11/11 Please read page 17 about Electric Eels. Write 3 sentences about what you learned and answer #1. Please use complete sentences.

17. Bell Work 5/12/11 Make a chart with at least 5 conductors and 5 insulators in it.

18. Bell Work 5/13/11 • What is electric potential? • What 3 factors affect how much electrical resistance an object has? • How can a lightning rod protect a building from fire?

19. Bell Work 5/16/11 • Why do lightning rods work better if they are placed high up, closer to the lightning charge? • Could the same material be used as both a conductor and an insulator? Explain your answer.

20. Bell Work 5/17/11 • Draw a picture of a wire with low resistance. • Draw a picture of a wire with high resistance. • What might wire made with low resistance be used in? • What might wire with high electrical resistance be used in?

21. Bell Work • How much resistance does a superconducting material have? (pg 24) • What is a ground cable? (pg 25)

22. 1.3 Notes Electric Current – the flow of charge (+,-) through a material. Electric currents produce magnetic fields --- spinning/moving electrons.

23. Circuit – complete path through which electric charges can flow. 1. circuit has a source of electrical energy. 2. circuits have devices that are run by electrical energy. 3. electric circuits are connected by conducing wires and a switch.

25. Ampere – the standard unit of measure for current Ohm’s law – shows relationship between current, voltage, and resistance Current = Voltage I = V Resistance R

26. Electric cell – produces electric current using the chemical or physical properties of different materials

27. Primary cell – produce electric current through chemical reactions until the chemicals are all used up Storage cell – produce electric current through chemical reactions that can be reversed in the battery

28. Bell Work 5/19/11 Make a Venn diagram comparing and contrasting electric current and static discharge.

29. Bell Work 5/24/10 Good morning. Please get out your study guide and begin reviewing for the final.

30. Bell Work • Where do solar cells get their energy? • What kind of battery can be charged by reversing chemical reactions? • What does an ohmmeter measure? • In which direction do electrons flow when a storage cell is being charged?

31. Bell Work 5/25/11 • An electrical pathway has a voltage of 240 volts and a current of 10 amperes. What is the resistance? • A 240-volt air conditioner has a resistance of 8 ohms. What is the current? • An electrical pathway has a current of 1.2 amperes and resistance of 40 ohms. What is the voltage?

32. Bell Work Write a paragraph about your favorite part of science class this year and your least favorite part of science class this year - Then get out your study guide and review

33. Magnetism – The attraction of a magnet for another object. Magnetic pole – end of a magnet, a pole is the area of a magnet where the magnetic effect is strongest. Pg 18 alike poles repel and opposites poles attract each other. Magnetic Fields - the region of magnetic force around a magnet.

37. Inside a Magnet Atom – smallest particle of an element that has the properties of that element. Element – Is on of about 100 basic materials that make up all matter. Nucleus – Center of an atom that contains the PROTON and the NEUTRON.

38. Proton – the positive charged particle of an atom. Neutron – Contain mass only (NO CHARGE). Electron – Very small particle Found circling the nucleus with a negative charge.

42. The spinning of the electrons in an atom causes an magnetic field. Magnetic domain – when a large portion of the atoms in a material are lined up in the same way. In a magnetized material all or most of the domains are arranged in the same direction. Iron is a substance that will undergo magnetism because the domains can be aligned to have a strong magnet.

43. Temporary magnets – when domains are alligned for a short period of time. Like placing a magnet on a group of paper clips

44. Permanent magnet – A magnet made of a material that keeps its magnetism. The more iron in the magnet the better (stronger) the magnet. Earth as a Magnet Although not completely understood the popular theory is --- the molten iron and nickel core is spinning causing the generation of a magnetic field around Earth. Earth has both a North and South magnet pole, just as a bar magnet does.

45. Magnetic Declination – the angle between geographic north (true north) and the north to which a compass needle points. • Magnetic north is 1250 km (776 miles) from geographic north. • Magnetosphere -

47. The Earth will actually make iron object magnetized over a long period of time, if the object doesn’t move. The rock that forms from lava will have a magnetic domain facing the poles of the Earth. Over 800,000 year the magnet poles of the Earth will swap. Don't know why, but da do!!!

49. Electric Current – the flow of charge (+,-) through a material. Electric currents produce magnetic fields --- spinning/moving electrons. Circuit – complete path through which electric charges can flow. 1. circuit has a source of electrical energy. 2. circuits have devices that are run by electrical energy. 3. electric circuits are connected by conducing wires and a switch.