Electromagnets

• What is generated when a current flows through a conducting wire?

  Magnetic field
• How can we prove that a magnetic field is produced around a wire?

  By using a compass that deflects when the current is on.
• What happens to the compass needle when the current is turned off?

  It lines up with the Earth's magnetic field.
• What effect does increasing the size of the current have on the magnetic field?

  A larger current produces a stronger magnetic field.
• How does the distance from the wire affect the strength of the magnetic field?

  The strength of the magnetic field decreases with distance from the wire.
• What happens to the direction of the magnetic field if the direction of the current is reversed?

  The direction of the magnetic field reverses.
• How can you determine the direction of the magnetic field produced by a wire?

  Use the right hand grip rule.
• What is a solenoid and how does it affect the magnetic field?

  • A solenoid is a coiled wire.
  • It produces a strong and uniform magnetic field when current flows.
  • The magnetic field resembles that of a bar magnet.
• How can you determine the direction of the magnetic field in a solenoid?

  Use the right hand grip rule with fingers curling in the current's direction.
• What are the three ways to increase the strength of the magnetic field produced by a solenoid?

  • Increase the size of the current.
  • Increase the number of turns of the coil.
  • Place a piece of iron inside the solenoid (iron core).
• What is an electromagnet?

  An electromagnet is a solenoid containing an iron core.
• What is a key advantage of using electromagnets?

  They allow for adjustable magnetic field strength and can be turned on or off.