Section 6- Magnetism and Electro-magnetism
- Created by: Penruddocke
- Created on: 22-01-15 00:18
View mindmap
- Section 6- Magnetism and Electro-magnetism
- Magnets and Magnetic Fields
- Magnets produce Fields
- Magnetism can be Induced
- Like poles repel each other
- Opposite Poles attact
- To see the magnetic field, you can get a bar magnet and lay a paper on top and put iron filing on top of it.
- Magnetic Field Line means the path strength of magnet
- Electro-magnetism
- A current- Carrying wire creates a magnetic Field
- There is a magnetic Field around a straight, current- carrying wire
- The magnetic field around a straight wire
- The Motor Effect
- It is a magnet exerting a force on the carry wireing
- This simple device shows that when an electrical current flows through a magnetic field, a force is exerted on the current. This force can be used to make an electric motor.
- Electric Motors and Loudspeakers
- A loudspeaker is a linear motor with a small range. It has a single moving coil that is permanently but flexibly wired
- The coil moves in the field of a permanent magnet, which is usually shaped to produce maximum force on the coil.
- Electric Motors only work on direct current
- This is because current only flows in one direction
- Electromagnetic Induction
- Electromagnetic induction occurs when a circuit with an alternating current flowing through it generates current in another circuit simply by being placed nearby.
- An alternating current is the kind of electricity flowing through power lines and home wiring, as opposed to a direct current, which we get from batteries.
- Faraday's Law. is the right hand rule
- Transformers
- Transformers change the voltage up and down
- They work by combining an oscillating electromagnets with another coil to induce
- Transformers only work on Alternating Current
- If the voltage decreases it is called a step down
- If the voltage increases it is called at step down.
- The ratio of turns= ration of the voltage
- Equation is Input (Primary) Voltage/ Output (secondary) Voltage= Number of turns on primary/ number of turns on secondary
- Magnets and Magnetic Fields
Comments
No comments have yet been made