Electromagnets

• What are the two poles of a magnet?

  North and south pole
• What distinguishes the north pole of a magnet?

  It is one of the two poles of a magnet
• How many poles does a magnet have?

  Two poles
• Why is it important to know about the poles of a magnet?

  They determine how magnets interact with each other
• What are electromagnets made of?

  Coil of wire around a magnetic core
• When do electromagnets work?

  When electricity flows through the coil
• How do electromagnets compare to permanent magnets?

  They are stronger than permanent magnets
• What shape of magnetic field do electromagnets produce?

  Same as a bar magnet
• How can you increase the strength of an electromagnet?

  Increase turns, current, or use better core
• What is one way to increase the strength of an electromagnet?

  Increase the number of turns on the coil
• What is another way to increase the strength of an electromagnet?

  Increase the current flowing through the coil
• What material can be used for a stronger electromagnet core?

  Iron instead of aluminium
• What are key terms related to electromagnets?

  • Attract
  • Core
  • Circuit breaker
  • Electromagnet
  • Electric bell
  • Lou
• How does an electric bell operate?

  The electromagnet attracts the iron armature
• What happens when the iron armature moves in an electric bell?

  It breaks the circuit, stopping current flow
• What occurs after the circuit is broken in an electric bell?

  The coil and core lose magnetism
• What happens to the spring in an electric bell after the circuit is broken?

  It returns to its original position
• What is the result of the electric bell's operation?

  The bell rings once
• What restarts the process in an electric bell?

  The circuit is complete again
• What do circuit breakers detect?

  Large changes in current in a house
• What happens when a large current flows in a circuit breaker?

  The electromagnet attracts an iron catch
• What is a benefit of circuit breakers?

  They can be reset and used again
• Why are circuit breakers suitable for home safety?

  They act as electrical safety devices
• How do loudspeakers use electromagnets?

  To generate sound through cone movement
• What creates sound waves in loudspeakers?

  Movement of the cone in and out
• What is a magnetic field?

  An area where magnetic materials experience force
• What does a permanent magnet have?

  Its own magnetic field
• What do magnetic field lines represent?

  The direction and strength of the magnetic field
• What indicates a stronger magnetic field?

  Closer magnetic field lines
• How can we find the shape of a magnetic field?

  Using plotting compasses or iron filings
• What does the Earth have that relates to magnetism?

  Its own magnetic field
• How does the Earth's magnetic field help us?

  It allows compasses to work for navigation
• What are the two poles of a magnet?

  North and south pole
• What do north poles do to south poles?

  North poles attract south poles
• What do south poles do to north poles?

  South poles attract north poles
• What do like poles do to each other?

  They repel each other
• What materials experience a magnetic force near a magnet?

  Magnetic materials like iron, nickel, cobalt
• What are the three magnetic metals?

  Iron, nickel, and cobalt