Motors and generators

• Current - the amount of charge transferred per second (e-/sec)
• Electrical energy - energy from moving e- (kinetic energy)
• Mechanic energy - energy from moving parts (kinetic energy)
• Chemical potential energy - energy stored in bonds
• Motor: electric - magnetic - motion
• Generator: motion - magnetic - electrical
• How does a motor work?

  1. as current flows through the coil, a magnetic field is generated (induced magnetic field)
  2. the induced magnetic field generated by the coil will interact with the permanent magnet causing turning of the coil
  3. the armature can be connected to blades that turn in a blow dryer
• Motors convert electrical energy into mechanical energy
• How are stronger motors built?

  1. increasing the number of couls
  2. increase the strength of the magnets
  3. changing the shape of the magnets
  4. increasing the voltage supplied
  5. by wrapping current carrying wire around a piece of metal like iron
• Generators have the opposite energy conversions as a motor and converts mechanical energy into electrical energy
• Electrical induction (producing a current) occurs when a coil moves next to a magnet or a magnet moves within a coil
• In the diagram, the coil is moving within a magnet and electricity is generated
• Mechanical energy usura a generator to produce electrical energy. Electrical energy uses a motor to produce mechanical energy
• alternating current (AC) - electrons flow in both directions in a circuit

  • examples - anything that plugs into a wall or generator
• Direct current (DC) - electrons flow in ONE direction in a circuit

  • examples - batteries and solar panels
• Batteries produce DC current, Generators produce AC current