Electromagnetic Induction

• Michael Faraday's experiment found that a changing magnetic field produces an electric current, but a magnetic field that doesn't change has no such effect.
• Fleming's left hand rule can be used to determine the direction of the force on a wire moving through a magnetic field
• Electric currents are made up of moving charges, they create magnetic fields
• An electromagnet is a coil of wires that becomes a magnet when electric current runs through it.
• Magnetic field could be converted into electric current.
• A galvanometer determines if there is a current and the direction of the flow of current.
• Electromagnetic induction is a phenomena when you change a magnetic field in a coil it induces in a voltage or a current.
• Determine the formula for magnetic flux:

  A) magnitude x area x cos theta

  
• The SI unit for magnetic flux is named after Wilhelm Weber.
• The SI unit for magnetic flux:

  A) Tm2

  B) Wb

  
• Magnetic flux depends on the magnitude of the magnetic field B, its orientation with respect to the surface, θ, and the area of the surface, A. A change in any of these variable results in a change in flux.​
• Loop 2 changes orientation relative to the field as it rotates.

  
• Determine the missing terms:

  A) number of loops

  B) rate of magnetic flux

  
• rate of magnetic flux = change in magnetic flux /change in time = ΔФ/Δt​
• The negative sign in Faraday's law indicates that the induced emf opposes the change in magnetic flux.
• The current that is induced as a result of the emf depends on the resistance of the circuit—just as in the case of a battery connected to a resistor.
• Determine missing terms:

  A) Resistance

  B) voltage

  
• Lenz's law states that an induced current always flows in a direction that opposes the change that caused it. 
• Determine the terms:

  A) magnetic force

  B) charge

  C) magnetic field line