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Ever see this? Winter migration.. • Canadian geese every year travel from the north into our region. They tend to follow predictable routes and patterns. • How do they find their way to where they are going? • As a group develop possible explanations for how they navigate. 2 minutes • Write down your explanation Winter migration.. • Using your devices, books, and articles gather more information regarding this topic. • SSW: Based on your new information adjust your answer accordingly. • What did you find?? SSW • On your notes make a list of EVERYTHING you know about magnets/magnetism (no matter how small or trivial). Magnets Day 2 Magnetism • What makes a magnet unique? • Objects that produce fields that attract or repel other objects. • What are the two ends of a magnet called? • Poles, North (+) and South (-) • What is attracted to a magnet? • Opposite poles (N to S or S to N) • Certain metals like Iron, steel, nickel, and cobalt • What is repelled by a magnet? • Same poles repel (N to N or S to S) Magnetism • What is a magnetic field? • magnet where the force of the magnet can act. • Can we see the magnetic field? • Not directly • How do we know the field exists? • We can see how it affects other objects. How does it work? • Remember everything that is matter has charges in them. However until those charges line up or move in the same direction they have very little force. Magnetic Force • With the charges lined up it creates a greater amount of force that can react at a distance. Magnets Day 3 Review • What are magnets attracted to? • What are the name of metals that are attracted to magnets? • What are magnets repelled by? • What is a magnetic field? • What gives a magnet its force? • How do we know there is a magnetic field if we cant see it? • Draw a diagram of the magnetic field lines of a bar magnet? ….we still didn’t solve yesterdays problem…… • How do we solve which side of your round magnets are really North or South? Compass •Field lines of earth’s magnetic field come together close to the planet’s North and South poles. •The north-seeking pole of the freemoving magnet in the compass points to Earth’s magnetic North Pole. Bird Migration Video • https://www.youtube.com/watch?v=4JUYyMHOHb 8 • https://phet.colorado.edu/en/simulation/magnetsand-electromagnets Types of Magnets • There are three types of magnets. • Permanent • Temporary • Electromagnet Permanent Magnets • These are naturally occurring pieces of a mineral called magnetite. It also has another name known as “lodestone”. • Key features: • • • • Naturally occurring Magnetic field cannot be turned off Magnetic field has a specific direction Must add more magnets to increase the field strength Magnets Day 4 Types of Magnets • There are three types of magnets. • Permanent • Temporary • Electromagnet Permanent Magnets • These are naturally occurring pieces of a mineral called magnetite. It also has another name known as “lodestone”. • Key features: • • • • Naturally occurring Magnetic field cannot be turned off Magnetic field has a specific direction Must add more magnets to increase the field strength Temporary Magnets • These are pieces of iron, steel, or cobalt that have been temporarily turned into a magnet. • Key features: • Occurs when a permanent magnet is rubbed along a piece of iron, steel, or cobalt • Magnetic field cannot be turned off, however it doesn’t last long • Magnetic field has a specific direction which is determined by the permanent magnet. • Field strength is determined by strength of permanent magnet used on it. What about a temporary magnet? Electromagnet What is electromagnetism? • (1820) Hans Christian Oersted produced a current in a wire during a lecture. • When he brought a compass near the wire, the compass changed direction. • Whenever he turned on the current in the wire, the compass needles lined up around the wire in the shape of a circle. Electric Current & Magnetism • Wherever there is electricity, there is magnetism • An electric current produces a magnetic field • This relationship is called electromagnetism What do they look like? • An electromagnets can be made out of a variety of materials but they all have the following: • Voltage source (battery or other source) • A ferromagnetic core • Wire wrapped around the core. This is known as a solenoid. As You Enter (no notes) 1) What does ferromagnetic mean? 2) Why does a compasses north needle face the south end of a magnet? 3) What happens inside an iron nail when you rub it against a magnet? 4) What is electromagnetism? Magnets Day 5 Electric Current & Magnetism • Wherever there is electricity, there is magnetism • An electric current produces a magnetic field • This relationship is called electromagnetism What do they look like? • An electromagnets can be made out of a variety of materials but they all have the following: • Voltage source (battery or other source) • A ferromagnetic core • Wire wrapped around the core. This is known as a solenoid. Electromagnet • The magnetic field produced by electrical current Key Features • The field can be turned on and off • The field can have its direction reversed • The field can have its strength changed Electromagnet • You can turn a magnetic field produced by a current on and off… • How can you turn the magnetic field off? • Simply by turning the current off! Electromagnet • You can change the direction of a magnetic field… • How can you change the direction? • Simply by reversing the direction of the current! Phet Electromagnet • You can increase the field of an electromagnet. 1. 2. 3. 4. Increase the current in the solenoid Add more loops of wire to the solenoid Wind the coils of the solenoid closer together Increase the strength of an electromagnet by using a stronger ferromagnetic material for the core Magnetic Levitation Mag Lev Day 6 Mag Lev • Using the 2nd Law of Electric Charges, Like charges repel, we can create things that float or levitate. Mag Lev • https://www.youtube.com/watch?v=1gMMM62NC -4 Mag Lev • More than just a parlor trick. Has been used to reduce friction in trains. MagLev trains do not have wheels, instead they have magnets that lift the train slightly so it floats. This means less friction which means it can go really fast (268mph). • https://www.youtube.com/watch?v=iaElPV0FWJ0 Standing Review • What is a magnet? • Where is the greatest force on a magnet? • What is attracted to a magnet? • What metals are ferromagnetic metals? • What is repelled by a magnet? • If we cant see a magnetic field, how do we know it exists? • Why does the north end of compass needle face the south end of a magnet? • Does a compass point to geographic north-ish? • Where could we find a permanent magnet? • Can we turn the field off on a permanent magnet? • What gives a magnet its field? • Can we switch the poles on a permanent magnet? • What does the field around a magnet look like? • Can we increase the strength of a permanent magnet? • What is a temporary magnet? Standing Review • What happens inside a temporary magnet? • What are the parts of an electromagnet? • Why doesn’t a temporary magnet stay magnetized very long? • How we turn the field of an electromagnet off or on? • Can I turn the field off and on in a temporary magnet? • How can I switch the poles of a temporary magnet? • How can we increase the strength of a temporary magnet? • Why does a compass line up with a wire that has electrical current? • What is electromagnetism? • How can we switch the poles of an electromagnet? • What are the 4 ways we can decrease the strength of an electromagnet? Magnets Mixing the two… • Lets look at what happens when we mix an electromagnet and a permanent magnet. Electric Motors Electric Motor • An electromagnet is the basis of an electric motor • An electric motor is all about magnets and magnetism: A motor uses magnets to create motion. • An electrical current running through a wire while inside a magnetic field causes motion. • Opposites attract and likes repel. Inside an electric motor, these attracting and repelling forces create rotational motion. • A motor is consist of two magnets. Vertical position of the loop: Rotation N S • https://www.youtube.com/watch?v=Q2mShGuG4R Y • https://www.youtube.com/watch?v=LAtPHANEfQo TRANSFORMERS Why do we need transformers? • In most cases, machines and appliances using electricity are manufactured to operate using a specific voltage and frequency. However, not all countries- and sometimes not all regions within the same country- generate the same voltage and frequency in their electricity. TRANSFORMERS • This is where transformers come in. Transformers adjust the voltage coming into the appliance to the proper level, and move it through the appliance to keep it running properly. TRANSFORMER • A transformer can change electrical energy of a given voltage into electrical energy at a different voltage level. It consists of two coils arranged in such a way that the magnetic field surrounding one coil cuts through the other coil. • Transformers can step up the voltage or step it down. • We step up voltage to send it over long distances • We step down voltage in order to use in houses This transformer's job is to reduce the 4160 volts down to the 240 volts that makes up normal household electrical service. It is a step down transformer http://science.howstuffworks.com/power3.htm Step Up Transformer at Power Plant TRANSFORMER • The factor which determines whether a transformer is a step up( increasing the voltage) or step down (decreasing the voltage) type is the "turns" ratio. The turns ratio is the ratio of the number of turns in the primary winding to the number of turns in the secondary winding. Step-up Transformer http://www.ibiblio.org/kuphaldt/electricCircuits/AC/AC_9.html • https://www.youtube.com/watch?v=ZjwzpoCiF8A • https://www.youtube.com/watch?v=VucsoEhB0NA EXIT TICKET • On a piece of paper answer the following questions: • Why do we need transformers? • How can you determine if it is a step up or step down transformer? • Why do we step up voltage? • Why do we step down? • https://www.youtube.com/watch?v=LAtPHANEfQo Bird Articles • https://www.allaboutbirds.org/the-basics-howwhy-and-where-of-bird-migration/ • http://nationalgeographic.org/media/how-dobirds-navigate/ • http://birding.about.com/od/birdbehavior/a/HowBirds-Migrate.htm • http://www.independent.co.uk/news/science/reve aled-secret-of-how-birds-navigate-duringmigration-818766.html • http://www.nytimes.com/2012/04/27/science/stu dy-sheds-light-on-how-pigeons-navigate-by-