- Electromagnets- if two currents travel in SAME direction, they ATTRACT; flux wants to get straighter and shorter. If two currents in OPPOSITE direction, they REPEL.
- Flux lines: flux density decreases as flux spacing increases. Current decreases the further away flux is.
You can strengthen an electromagnet by :
- more coil turns
- increase current. Φ= ANI
- increase permeability by using a soft iron core (permeability: the permeance of 1m² of a material.) A= µA/L. To increase permeability, increase surface area, decrease length.
- decrease the air gap around the magnet: flux can also occur through air (flux leakage)
- Motors convert electrical energy --> kinetic energy. Use left hand rule.
- Generators convert kinetic energy --> electrical energy. Use right hand…