QCEphysics

Magnetic Fields

define the term magnetic field

- Magnetic field is a region of space where a magnetic force is experienced

• Magnets are always dipolar and a magnetic field is a dipolar field (have south and north poles)

recall how to represent magnetic field lines, including sketching magnetic field lines due to a moving electric charge, electric currents and magnets

Direction - north to south

1. Positive charge moves down the page, as the force is acting down
2. Negative charge moves up the page, as the force is acting down
3. Negative charge moves up the page, as the force is acting up 

recall that a moving electric charge generates a magnetic field

determine the magnitude and direction of a magnetic field around electric current-carrying wires and inside solenoids solve problems involving the magnitude and direction of magnetic fields around a straight electric current-carrying wire and inside a solenoid

Ampere's right-hand rule is used for current-carrying wires and solenoids (in solenoids the thumb points towards north, and fingers curl in the direction of conventional current)

• Unit of magnetic field strength is tesla (T)

recall that electric current-carrying conductors and moving electric charges experience a force when placed in a magnetic field solve problems involving the magnetic force on an electric current-carrying wire and moving charge in a magnetic field.

Fleming's left-hand rule is used for moving electric charges or current-carrying conductors

Students should be able to recall that electric charge is conserved at all points in an electrical circuit (Unit 1 Topic 3: Electrical circuits).

- The Law of Conservation of charge states that electric charge can neither be created nordestroyed

- For motors - electrical energy to mechanic al energy