Electromagnetism

Electromagnetism

Multiple Choice

The picture is an example of an:

• Electric circuit
• Electromagnet
• Electric nail
• Electric power cell

Multiple Choice

Increasing the number of coils in an electromagnet will _________ the power of the magnet.

• decrease

• increase

• not affect

Multiple Choice

How do you make an electromagnet stronger?

• Add a motor and/or lightbulbs
• Add more light bulbs and/or wire coils
• add more wire coils and/or a switch
• add more wire coils and/or batteries

Multiple Choice

To make this electromagnet stronger you could:

• use less wire

• have fewer wire coils around the nail

• have more wire coils around the nail

• use a plastic core

Multiple Choice

What is formed when a wire in an electric circuit is wrapped around an iron core producing a magnetic field?

• electromagnet
• generator
• magnet
• electric motor

Multiple Choice

Electric motors are devices that convert _____ energy into  _____ energy.

• electrical; mechanical
• mechanical; electrical
• chemical; potential
• mechanical; kinetic

Multiple Choice

Which best describes how a motor works?

• When a fan blows on a wire, it causes it to spin, creating a force.

• When a fan blows on a wire, it causes it to spin, creating an electrical current.

• When a wire that carries electrical current is placed in zero gravity, the wire experiences a force.

• When a wire that carries electrical current is placed in a magnetic field, the wire experiences a force.

Multiple Choice

Which statement best explains the flow of energy through a motor?

• battery-->electrical current-->copper wire rotor -->magnet--> mechanical energy

• battery--> magnet--> electrical current--> copper wire rotor--> mechanical energy

• magnet--> mechanical energy--> copper wire rotor--> battery--> electrical current

• magnet--> copper wire rotor--> mechanical energy--> battery--> electrical current

Multiple Choice

The process of generating the current in a conductor is called as

• Electro motive force

• Electromagnetic induction

• generator energy conversion

• induced voltage

Multiple Choice

Generators are devices that convert _____ energy into _____ energy.

• chemical; mechanical
• mechanical; electrical
• electrical; mechanical
• potential; kinetic

Multiple Choice

What energy do you put IN to a generator?

• Mechanical
• Electrical
• Thermal
• Potential

Multiple Choice

What type of energy comes OUT of a generator?

• Mechanical
• Electrical
• Thermal
• Potential

Multiple Choice

What is the best energy chain for coal fired power plants

• chemical -> kinetic -> electrical
• kinetic -> electrical
• electrical -> chemical -> heat
• kinetic -> chemical -> electrical

Multiple Choice

In a _______ a spinning turbine moves magnets which generates an electric current.

• Motor

• Generator

Multiple Choice

Which is the best energy chain for nuclear power plants?

• Thermal -> kinetic -> electrical
• light -> kinetic -> thermal
• thermal -> electrical
• light -> kinetic -> electrical

Multiple Choice

The function of a transformer is to ...

• raise and lower the apparent power levels

• transfer DC voltage from the primary winding to the secondary winding

• increase or decrease A.C voltage or A.C current levels

• transform mechanical energy into electrical energy

Multiple Choice

If a transformer increases voltage, it is called a ......... transformer.

• step right

• step left

• step up

• step down

Multiple Choice

If a transformer reduces voltage, it is called a....................... transformer.

• step left

• step right

• step up

• step down

Multiple Choice

This picture is an example of a ___________

• Step- Up Transformer
• Step- Down Transformer
• Motor
• Generator

Multiple Choice

A step-down transformer has an input voltage of 50 V. The output voltage will be...

• less than 50 V

• 50 V

• greater than 50 V

Multiple Choice

A step-up transformer has more turns on the primary coil than the secondary coil.

• True

• False