magnetism

• What causes magnetic forces between magnets?

  Invisible magnetic fields
• What is a magnetic field?

  The region around a magnet where another magnet or magnetic material feels a force
• Which materials are considered magnetic materials?

  Iron, nickel, cobalt, and steel
• What are the two poles of a magnet called?

  North pole (N) and south pole (S)
• What happens when the south pole of one magnet is close to the north pole of another magnet?

  The south pole will attract the north pole
• What is the formula for calculating force in a magnetic field?

  F = magnetic flux density (T) x current (A) x length (m)
• What does the variable F represent in the formula F = B x I x l?

  Force (N)
• What does the variable B represent in the formula F = B x I x l?

  Magnetic flux density (T)
• What does the variable I represent in the formula F = B x I x l?

  Current (A)
• Under what condition does the formula F = B x I x l apply?

  When the wire is at right angles to the magnetic field
• What does magnetic flux density measure?

  The strength of the magnetic field
• What happens to a conductor that is at right angles to the magnetic field?

  It experiences a force
• In the left hand rule, which finger represents the direction of the magnetic field?

  First finger
• In the right-hand rule, which finger represents the direction of the current?

  Second finger
• In the right-hand rule, which finger represents the direction of the force?

  Thumb
• What is the direction of the magnetic field in the left-hand rule?

  From North to South (N to S)
• What is the direction of conventional current in the right-hand rule?

  From positive to negative (+ to -)