Lesson Plan: P2.5.03

Learning About
What is meant by the motor effect?

Keywords:

Current: An electric current is a flow of electric charge. (1)
Magnetic field (1)
motor effect: The motor effect is the term used when a current-carrying wire in the presence of a magnetic field experiences a force. (1)
Magnetic field: a region around a magnetic material or a moving electric charge within which the force of magnetism acts. (1)
Current: A flow of electrons (charge). (1)
Conductor: A material the can conduct electricity or thermal energy. (1)

Memory Anchor:

Method	Precise Learning Objective	Linked	Question / Activity (Designed for maximum working out)	Stepping Stones	Pitstop Check (Thinking Map)
	When a conductor carrying a current is placed in a magnetic field the magnet producing the field and the conductor exert a force on each other. This is called the motor effect.		(HT only) What is meant by the motor effect? Explain what is meant by the motor effect. Explain why a motor spins with respect to the magnetic field. Make an electric motor and investigate how the speed and direction of rotation can be changed.
	Students should be able to show that Fleming's left-hand rule represents the relative orientation of the force, the current in the conductor and the magnetic field.
	Students should be able to recall the factors that affect the size of the force on the conductor.		What factors affect the size of the forces on the conductor?
	For a conductor at right angles to a magnetic field and carrying a current: force = magnetic flux density ? current ? length F = B I l force, F, in newtons, N magnetic flux density, B, in tesla, T current, I, in amperes, A (amp is acceptable for ampere) length, l, in metres, m		How is magnetic flux density calculated? Include SI units.

Links To the Big Ideas
Forces	Particles	Energy	Cells