electromagnets

• What should you be able to describe by the end of the video?

  How current generates a magnetic field
• What does a solenoid do to the magnetic effect of a current?

  It increases the magnetic effect
• What can you draw related to a straight wire and a solenoid?

  The magnetic field pattern
• What happens when the switch in the circuit is closed?

  An electric current flows around the circuit
• What does the diagram show when the current is flowing?

  The conventional current direction
• What is produced around a conducting wire when current flows?

  A magnetic field is produced
• How can we prove the existence of a magnetic field around a wire?

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

  It lines up with the earth's magnetic field
• What occurs when the current is turned on again?

  The compass needle deflects
• How does the strength of the magnetic field relate to the size of the current?

  A larger current produces a stronger field
• What happens to the magnetic field strength as you move further from the wire?

  The strength decreases
• What happens if we change the direction of the current?

  The direction of the magnetic field changes
• How do you determine the direction of the magnetic field produced by a wire?

  Using the right hand grip rule
• What does the thumb represent in the right hand grip rule?

  The direction of the conventional current
• What do the fingers represent in the right hand grip rule?

  The direction of the magnetic field
• What shape does coiling the wire create?

  A solenoid shape
• What type of magnetic field does a solenoid produce?

  A strong and uniform magnetic field
• How does the magnetic field around a solenoid compare to that of a bar magnet?

  It has a similar shape
• How can you determine the direction of the magnetic field in a solenoid?

  Using the right hand grip rule
• What does placing your fist in the right hand grip rule indicate?

  The direction of the north pole
• What are the three ways to increase the strength of the magnetic field in a solenoid?

  Increase current, turns, or add iron core
• What happens if we increase the size of the current in a solenoid?

  The strength of the magnetic field increases
• How does increasing the number of turns of the coil affect the magnetic field?

  It increases the strength of the magnetic field
• What is an iron core used for in a solenoid?

  To increase the strength of the magnetic field
• What is a solenoid containing an iron core called?

  An electromagnet
• What is a key advantage of electromagnets?

  We can change the strength of the magnetic field
• How can we turn an electromagnet on or off?

  By changing the size of the current
• Where can you find plenty of questions on electromagnets?

  In the vision workbook