Science Notes: Stnd 01 Date Standard 01: 8.PS2.1 Magnetism and Electricity Design and conduct investigations depicting the relationship between magnetism and electricity in electromagnets, generators, and electrical motors, emphasizing the factors that increase or diminish the electric current and the magnetic field strength. Science and Engineering Practice(s) Develop and Use Models, Obtain and communicate information, Construct Explanations Crosscutting Concepts Cause and Effect, Systems and Systems Models I Can Statement ...I can explain and demonstrate cause and effect relationships between magnetism and electricity.

Magnetism and Electricity Notes Stnd 01: Magnetism and Electricity Science Magnetic Fields An invisible magnetic field exists around all magnets. N S

One end is the North Pole. Other end is the South Pole. Magnetic Fields You can see the magnetic field lines by using fine iron filings. Note: field lines are concentrated at the ends (called poles) One end is the North Pole. Other end is the South Pole. North Pole South Pole

Magnetism and Electricity Notes Stnd 01: Magnetism and Electricity Science North and South Poles All magnets have these poles regardless of their shape. If you cut a magnet in half, each half will still have these two poles (north and south) Bar magnet Horseshoe Magnet Donut magnet

F.Y.I: Why Are Some Substances Magnetic? All atoms have magnetic fields with north and south poles. Atoms in objects are found in areas called domains. If the poles line up facing the same direction, this makes the object magnetic. If they don’t line up, it is not magnetic.

Magnetism and Electricity Notes Stnd 01: Magnetism and Electricity Science Magnetic Forces magnets exert force on other magnets “Opposites attract” (North & South pull towards each other) N S “Like repels” (North & North or South & South push away) N S

Electromagnets Electric current in the wire produces a magnetic field which lines up atoms in the domains of the iron core forming an electromagnet. Simple Electromagnet Iron Core Source of Electricity Solenoid An electromagnet consists of a solenoid wrapped around an iron core attached to a source of electricity

(1) Move it faster or (2) Add more coils. Simple Electrical Generator Electromagnetic Induction Magnets and a coil of wire can induce (generate) electricity The magnet has to move through the coil (solenoid) … or the coil has to move through the magnet To Increase the Current: (1) Move it faster or (2) Add more coils. Simple Electrical Generator Coil of Wire (Solenoid) Bar Magnet

Rotational Generators (very common) Note: the magnet is stationary and the wire coil is rotating. It also works if the wire is stationary and the magnet is moving Rotational Generator Magnet Magnet Wire Coil

How It Works All magnets have an invisible magnetic force field. The bar magnet is pushed back and forth through the solenoid Simple Electrical Generator The magnetic force field pushes the electrons from atom to atom in the wire creating electrical current.

F.Y.I.-Electromagnetic Induction …is how most electricity is generated around the world. These power plants all use magnets and coils of wire to make electricity Nuclear Power Plant Wind Turbines Coal Power Plant Hydroelectric Dam

F.Y.I.-Electromagnetic Induction …is how most electricity is generated in cars, trains, boats, & planes Each of these machines has a generator inside that creates electricity Electrical Generator (Alternator) Consists of a magnet rotating through a coil of wire

Electrical Motors Electrical motors change electrical energy into mechanical energy. In other words, they use electricity to make things move. Most common movement: rotary motion To Increase the Output (Torque): (1) Use more current (2) Add more coils (3) Use stronger magnets

Are commonly used in a great variety of devices Electrical Motors Are commonly used in a great variety of devices Blenders RC (Toy) Cars Hairdryers Electric Shavers Electric Fans Washers and Dryers Laptop Fans

Are commonly used in a great variety of machines Electrical Motors Are commonly used in a great variety of machines Flying Drones Underwater Drones Robotic Explorers Submarines Electric Cars Electric Trains

Electrical Motor Details Various Types: AC motors, DC motors, induction motors, brushed motors, brushless motors, stepper motors, etc. Three Motor Components: Stator, Rotor, Commutator, What does the stator do? (Look it up online!) What does the rotor do? (Look it up online!) What does the commutator do? (Look it up online!)