Magnetism and Electromagnetism - Electromagnetic Induction

Question 1

when is voltage induced in a conductor/coil?

Answer 1

when a conductor experiences a changing magnetic field a potential difference or voltage is induced in it. the strength of the potential difference depends on the strength of the magnetic field, how fast it changes (how fast the coil is spinning), and how much of the conductor is exposed to the field (how many turns)

Question 2

how can eletricity be generated?

Answer 2

electricity can be generated by either moving a magnet inside a coil of wire or rotating a coil inside a permanent magnetic field

Question 3

how is energy generated by moving a magnet inside a coil of wire?

Answer 3

• magnet is rotated within a coil
• as it turns the coil cuts the constantly changing magnetic field lines from the magnet.
• this induces a voltage (or current) in the coil.
• this can then be connected to an existing circuit.
• in a generator, energy is being converted from kinetic (mechanical) energy into electrical energy
• the size of the induced voltage (or current) can be increased by: using a stronger magnet, having more turns in the coil or spinning/moving the magnet faster

Question 4

how is energy generated by rotating a coil inside a permanent magnetic field?

Answer 4

• a coil is rotated within a magnetic field
• as it turns the coil cuts the magnetic field lines.
• this induces a voltage (or current) in the coil.
• this can then be connected to an existing circuit.
• in a generator, energy is being converted from kinetic (mechanical) energy into electrical energy.
• the size of the induced voltage (or current) can be increased by: using a stronger magnet, having more turns in the coil or spinning/moving the coil faster