Magnetism

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

  The forces produced when magnets are brought together
• What is the difference between permanent and induced magnets?

  A permanent magnet produces its own magnetic field, while an induced magnet becomes a magnet in a magnetic field
• What are the two ends of a bar magnet called?

  North Pole and South Pole
• Where are the magnetic forces strongest on a magnet?

  At the poles of the magnet
• What happens when two like poles of magnets are brought close together?

  They repel each other
• What occurs when unlike poles of magnets are brought close together?

  They attract each other
• What type of forces are the attraction and repulsion between two magnetic poles?

  Non-contact forces
• What does a permanent magnet produce?

  Its own magnetic field
• What happens when a permanent magnet is brought close to another permanent magnet?

  They can attract or repel each other depending on their orientation
• What is an induced magnet?

  An object that becomes a magnet when placed in a magnetic field
• What happens to objects when a permanent magnet is placed between them?

  They become induced magnets
• What is a key fact about induced magnetism?

  It always causes a force of attraction
• What happens to induced magnets when the permanent magnet is removed?

  They lose most or all of their magnetism quickly
• What are the key concepts related to permanent and induced magnets that students should focus on for revision?

  • Permanent magnets produce their own magnetic field.
  • Induced magnets become magnets in a magnetic field.
  • Induced magnetism always causes attraction.
  • Induced magnets lose magnetism when the magnetic field is removed.
• What should you be able to describe by the end of the video on magnetic fields?

  You should be able to describe magnetic fields, how to plot their patterns, and evidence of Earth's core magnetism.
• What is meant by a magnetic field?

  A magnetic field is a region around a magnet where a force acts on another magnet or on a magnetic material.
• How can you plot the magnetic field pattern of a magnet?

  By using a compass to trace the direction of the magnetic field lines around the magnet.
• What are the two types of magnets mentioned?

  Permanent magnets and induced magnets.
• What is an induced magnet?

  An induced magnet is a material that becomes a magnet when placed in a magnetic field.
• What is a permanent magnet?

  A permanent magnet always has a magnetic field.
• What are the four types of magnetic materials?

  Iron, steel, cobalt, and nickel.
• Where is the magnetic field strongest in a magnet?

  The magnetic field is strongest at the poles of the magnet.
• How can the direction of a magnetic field be found?

  The direction of a magnetic field can be found using a magnetic compass.
• How does the strength of a magnetic field change with distance from the magnet?

  The strength of the magnetic field decreases as the distance from the magnet increases.
• What happens when a compass is placed near a bar magnet?

  The compass needle aligns itself with the magnetic field of the bar magnet.
• What is the cause of the Earth's magnetic field?

  The Earth's magnetic field is due to the Earth's core.
• What are the key points about magnetic fields and magnets?

  • Magnetic fields are regions around magnets where forces act.
  • Types of magnets: permanent and induced.
  • Four magnetic materials: iron, steel, cobalt, nickel.
  • Strength of magnetic field decreases with distance.
  • Strongest at the poles.
  • Direction found using a compass.
  • Earth's magnetic field is due to its core.
• What does it indicate if the compass needle always points in the north-south direction when held away from any magnets?

  It indicates that the Earth has its own magnetic field.
• What should you be able to describe by the end of the video?

  How a current flowing through a wire generates a magnetic field
• What effect does a solenoid have on the magnetic field of a current?

  A solenoid increases the magnetic effect of a current
• What should you be able to draw related to magnetic fields?

  The magnetic field pattern for a straight wire carrying a current and for a solenoid
• What happens when the switch in an electrical circuit is closed?

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

  A magnetic field is produced around the wire
• How can we prove that there is a magnetic field around a wire?

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

  The compass needle lines up with the earth's magnetic field
• What occurs to the compass needle when the current is turned on?

  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 magnetic field
• What happens to the strength of the magnetic field as you move further from the wire?

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

  The direction of the magnetic field changes
• What rule do we use to determine the direction of the magnetic field produced by a wire?

  The right hand grip rule