Physics - Electromagnetic Induction

Question 1

What is induced when there is a change is magnetic field or when wire cuts a magnetic field?

Answer 1

A voltage is created, a magnetic field is simply a movement of charge, this means that as voltage is the pushing force behind charge then a voltage is created when there is a change in magnetic field

Question 2

What affects the strength of an induced voltage?

Answer 2

• The size of the magnetic field of which it is passing through
• The length of the wire passing through the magnetic field
• The speed that the conductor passes through the magnetic field
The larger the magnetic field that the conductor passes through the more flux lines that the conductor will pass through meaning that it will create a higher voltage, the higher the speed it passes through these means that a higher voltage is induced.

Question 3

How do AC generators work?

Answer 3

It is very similar to a DC generator but to be able to generate voltage in alternating directions the current must always remain flowing through the same direction of the coil so as it passes up through the more north side of the magnetic field it generates a positive voltage, then when it moves down the more south end it generates a negative voltage.
This means that it needs 2 split ring commutators

Question 4

Factors that affect AC generators:

Answer 4

• Number of coils in the loop
• Increasing the strength of the magnetic field
• Perscence of a soft iron core
• Frequnecy of rotation
• The current through the coil

Question 5

What is the shape of the graph of the output voltage of an AC generator?

Answer 5

Very similar to a sine graph