Magnetism and Electromagnetism

What are the two types of magnetic poles?

• Positive and Negative

• North and South

• Left and Right

• Up and Down

In which direction do magnetic field lines travel?

• From east to west

• From north pole to south pole outside the magnet, and from south pole to north pole inside the magnet

• From top to bottom

• From south to north

Explain the concept of electromagnetism.

• The interaction between sound waves and light waves.

• The interaction between electric currents or fields and magnetic fields.

• The process of converting mechanical energy into electrical energy.

• The study of the Earth's magnetic field.

Name two common magnetic materials.

• plastic, wood

• iron, nickel

• silver, gold

• copper, aluminum

Describe the process of magnetising a magnet.

• Rubbing it with another magnet or exposing it to a strong magnetic field

• Dipping it in water

• Covering it in oil

• Exposing it to extreme heat

Explain how a magnet can be demagnetised.

• Spraying it with water

• Heating it to a high temperature or subjecting it to a strong external magnetic field in the opposite direction.

• Dropping it from a height

• Exposing it to sunlight

What happens to the magnetic field when a magnet is cut into two pieces?

• The magnetic field becomes stronger in each piece

• The magnetic field becomes weaker in each piece

• The magnetic field disappears completely

• The magnetic field remains in each piece, creating two separate magnetic fields.

What is the role of electromagnets in everyday devices?

• They generate electricity for devices.

• They produce heat for devices.

• They create magnetic fields for the operation of devices.

• They control the volume of devices.

How does the Earth act as a giant magnet?

• The Earth's magnetic field is generated by the rotation of the planet.

• The Earth's core is made of molten iron and nickel, which creates a magnetic field.

• The Earth's magnetism is caused by the gravitational pull of the moon.

• The Earth's core is made of wood and plastic, which creates a magnetic field.

What is the process of demagnetizing a magnet?

• Exposing it to extreme cold temperatures

• Heating it to a high temperature or subjecting it to a strong external magnetic field in the opposite direction

• Submerging it in water for an extended period

• Exposing it to bright sunlight