Magnetic Fields
This is the invisible area around a magnet where magnetic forces act.
What is a magnetic field?
What happens when opposite magnetic poles face each other?
What is attract?
Which material is most likely to be attracted to a magnet?
What is iron?
A magnet created using electricity is called this.
What is an electromagnet?
What type of energy is stored between magnets?
What is magnetic potential energy?
This law explains how magnetism can produce electricity.
What is Faraday’s Law?
Magnetic field lines always flow in this direction.
What is from north to south?
What happens when the same magnetic poles face each other?
What is repel?
Name three elements that can form a permanent magnet.
What is iron, nickel, and cobalt?
What creates a magnetic field around a wire?
What is moving electric charges?
What happens to potential energy when repelling magnets are pushed closer together?
What is it increases?
What must happen to a magnetic field to create electric current?
What is it must change?
These tools can be used to visualize magnetic fields.
What are iron filings or a compass?
Which situation shows attraction: N–S or N–N?
What is N–S?
Why are plastic and wood not attracted to magnets?
What is because they do not have unpaired electrons?
Why can electromagnets be turned on and off?
What is because they require electric current?
When magnets move apart, potential energy becomes this type of energy.
What is kinetic energy?
Which device uses Faraday’s Law: a battery or a generator?
What is a generator?
True or false: Magnetic field lines can cross each other.
What is false?
Which situation shows repulsion: S–S or N–S?
What is S–S?
What makes some materials magnetic and others not magnetic?
What is because:
- Not all materials have unpaired electrons
- Not all materials have electrons that spin/align in the same direction
What happens to an electromagnet when the current stops?
What is it stops being magnetic?
How does distance affect magnetic force?
What is force increases as distance decreases?
Why does a moving magnet create current but a stationary magnet does not?
What is because only changing magnetic fields induce current?
What does it mean when magnetic field lines are close together?
What is a stronger magnetic field?
Why do magnets move when released near each other?
What is:
- Because magnetic forces act between them
- Because the magnetic field between them causes either repulsion or attraction
Why do only some metals form permanent magnets?
What is because only some have unpaired electrons that align?
Name one device that uses an electromagnet.
What is a motor, speaker, doorbell, or crane?
Why do magnets released from closer distances move farther?
What is because they have more potential energy?
What motion is required for Faraday’s Law to work?
What is relative motion between magnet and wire?
Why do magnetic field lines never cross?
What is because each point in space has only one magnetic field direction?
If two repelling magnets are pushed closer together, what happens to the potential energy between them?
What is it increases?
What atomic feature causes magnetism to cancel when electrons pair up?
What is paired electrons have opposite spins?
How does adding more coils affect an electromagnet?
What is it makes the magnetic field stronger?
Why does stronger magnetic force result in greater motion?
What is because more energy is transferred into motion?
How does increasing the speed of a moving magnet affect induced current?
What is it increases the current?
How does the magnetic field explain why magnets can move objects without touching them?
What is the magnetic field applies a force at a distance?
What happens to potential energy when a two magnets are released near each other? What happens to the energy once there is a collision?
When the magnets start to move, the potential energy turns into kinetic energy and then once they collide, it turns into thermal energy.
What causes the Earth to be magnetic?
Movement of the Iron in Earth's outer core causes Earth to have a magnetic field.
Explain why coiling the wire increases the strength of an electromagnet.
What is because the magnetic fields from each loop add together?
Explain the relationship between distance, force, and magnetic potential energy.
What is smaller distance causes stronger force and more potential energy?
Explain how Faraday’s Law is used in power plants to generate electricity.
What is turbines spin magnets or coils to change magnetic fields and induce current?