Electricity and Magnetism Chap 2-3

List 3 ways to induce an electric current in a wire?

1-moving a magnet into a coil of wire 2-moving a wire between the poles of a magnet 3-turning a loop of wire between the poles of a magnet

What does a transformer do?

A transformer increases or decreases the voltage of alternating current.

How are an electric generator and a transformer different?

An electric generator changes mechanical energy into electrical energy through electromagnetic induction while a transformer changes the voltage of alternating current through electromagnetic induction.

What was Faraday trying to do in his experiment?

He was trying to induce a current in a wire by using the magnetic field of an electromagnet.

How does a generator produce an electric current?

It rotates a coil of wire through a magnetic field. This motion induces an electric current in the wire.

What energy change happens in an electric generator?

Mechanical energy is converted into electrical energy in an electric generator.

Explain why rotating either the coil or the magnet in a generator induces and electric current.

When either of them is moving there will be a change in the magnetic field in the coil and the changing magnetic field is what induces and electric current in the wire.

electric generator:

a device that converts mechanical energy into electrical energy

transformer:

a device that increases or decreases the voltage of alternating current

What are three sources of energy that are used to generate electrical energy?

a nuclear reaction, fossil fuels, and wind

In a step-down transformer, does the primary or secondary coil have more loops?

step-DOWN - has more coils in the primary coil (number of coils goes DOWN)

In a step-up transformer, does the primary or secondary coil have more loops?

step-UP - has more coils in the secondary coil (number of coils goes UP)

A transformer has 3,000 loops in its primary coil and 1,500 loops in its secondary coil. Is this a step-up or a step-down transformer and what is the voltage in the secondary coil if the voltage in the primary coil is 120V?

step-down because there are less loops in the secondary coil than the primary coil (120V/3,000 loops) X 1,500 loops = 60V

A transformer has 500 loops in its primary coil and 5,000 loops in its secondary coil. Is this a step-up or step-down transformer and what is the voltage in the primary coil if the voltage in the secondary coil is 20,000 V?

step-up because there are more loops in the secondary coil than the primary coil (20,000 V/5,000 loops) X 500 loops = 2,000 V

electromagnetic induction:

the process of creating a current in a circuit by changing a magnetic field