Transcript magnetic
Bellwork SPI 0807.9.12 Acids and Bases Jan 14, 2013 1) First go get you clickers 2) Then get a copy of the 6-question bellwork assignment from the front table 3) Next head your paper and number from 1 to 6 Yes, skip after every third number as usual 4) Answer the questions. Use your book to help you (ps368 to 373) 1 Notes SPI 0807.9.12 Acids and Bases The pH scale -pH scale: a way to determine the level of acidity or basicity of a substance. -Acids are 0 to 6.9 &bases are 7.1 to 14 on the pH scale -7 is neutral (pure water is 7) 72 Today’s Plan SPI 0807.9.12 Acids and Bases SPI 0807:12.1 to 12.3 Electricity and Magnetism 1) Discuss objective(s), bell work, ask about birthdays. 2) Discuss most missed answers 3) Grade acid and base foldables with CPS clickers 4) Collect signed report cards 5) View notes about electromagnetism 6) Copy this into your agenda! No Homework Silly Thought Remember, light travels faster than sound. This is whys some people appear bright until they speak 2 Notes SPI 0807:12.1 to 12.3 Electricity and Magnetism Notes: Magnets and Electricity • Magnetic Poles: are points on a magnet that have opposite magnetic qualities. • North and South: The pole that points to the north is called the magnet’s north pole. The opposite end of the magnet, called the south pole, points to the south. •Magnetic Forces: magnets each exert a magnetic force on other magnet due to spinning electric charges in the magnets. “Opposites” attract and “Like” repels Notes SPI 0807:12.1 to 12.3 Electricity and Magnetism Properties of Magnets, continued • Magnetic Fields: An invisible magnetic field exists around magnets. However, you can see the magnetic field lines of a magnet by using fine iron filings. •(See Ch. 16: Sect 1 VC) Notes Notes SPI 0807:12.1 to 12.3 Electricity and Magnetism The Cause of Magnetism • Atoms and Domains: In materials such as iron, nickel, and cobalt, groups of atoms are in tiny areas called domains. The north and south poles in a domain line up and make a strong magnetic field. Notes SPI 0807:12.1 to 12.3 Electricity and Magnetism (See Ch. 16: Sect 1 VC and p430: Fig 10) SPI 0807:12.1 to 12.3 Electricity and Magnetism Electromagnetism • In 1820 it was discovered that electric current produces a magnetic field. •Electromagnetism: Is the interaction between electricity and magnetism. (See VC) • A solenoid: is a coil of wire that produces a magnetic field when carrying an electric current. (VC or p433: Fig 2) • An electromagnet: is made up of a solenoid wrapped around an iron core. (see p434: Fig3) • Turning Electromagnets On and Off: Electromagnets are very useful because they can be turned on and off as needed. The solenoid has a field only when there is electric current in it.