Magnets and magnetic fields

• What is happening to Lagos' population?

  It is growing rapidly
• Why has Lagos' population grown?

  For different reasons at different times
• What are the characteristics of magnets and magnetic fields?

  • Magnets have two poles: north and south
  • All magnets produce a magnetic field
  • Magnetic field strength varies with distance from the magnet
• How many poles do all magnets have?

  Two poles: north and south
• What does a magnetic field produce?

  A magnetic field produces a force
• How do magnetic field lines behave?

  They always go from north to south
• What happens to the strength of a magnetic field as you move away from a magnet?

  The field becomes weaker
• What is the capital of Nigeria?

  Lagos
• What is the reason for Lagos' rapidly growing population?

  Different reasons at different times
• What are the two poles of a magnet called?

  North and south
• Why do all magnets have two poles?

  Magnets always have a north and south pole
• How can you show the direction of a magnetic field?

  By drawing magnetic field lines
• What do the magnetic field lines indicate about the direction of the magnetic force?

  The field lines show the direction a north pole would be pushed
• What is the relationship between the strength of a magnetic field and the closeness of the field lines?

  The closer the field lines, the stronger the magnetic field
• Where is the magnetic field strongest around a magnet?

  At the poles
• What happens when the north and south poles of two magnets are brought close together?

  They will attract each other
• How should you draw magnetic field lines between two bar magnets placed near each other?

  Draw parallel lines going from the north to south poles
• What are the key properties of magnetic fields?

  • Magnetic fields have north and south poles
  • Magnetic fields exert forces on other magnets or magnetic materials
  • Magnetic field lines show the direction and strength of the field
  • Magnetic fields are strongest at the poles and weaker further away
• What is the purpose of a compass?

  To show the direction of the Earth's magnetic field
• How can you use a compass to map out a magnetic field?

  1. Place the compass inside the magnetic field
  2. The compass needle will align with the direction of the field lines
  3. Draw lines connecting the tips of the compass needles to map the field
  4. The closer the field lines, the stronger the magnetic field
• How do the magnetic forces between two magnets differ when their poles are the same versus when they are opposite?

  Like poles repel, opposite poles attract
• What do compasses show?

  The directions of magnetic fields
• What is inside a compass?

  A tiny bar magnet called a needle
• How does a compass needle align?

  It always lines up with the magnetic field
• How can you use a compass to build a picture of a magnetic field?

  • Place the magnet on a piece of paper
  • Draw around it
  • Position the compass near the magnet
  • The needle will point in the direction of the field
  • Mark the direction with dots
  • Repeat at different points around the magnet
• What should you do after marking the direction of the compass needle?

  Join the marks to create field lines
• What direction does the compass needle point towards?

  Towards the south pole of the magnet
• What happens when compasses are not near a magnet?

  They point towards Earth's North Pole
• Why do compasses point towards the Earth's North Pole?

  Because Earth generates its own magnetic field
• What analogy is used to describe magnets in relation to farmers?

  Magnets are like farmers surrounded by fields
• What should you learn about magnetic fields?

  Basic principles of magnetic fields
• How do you draw magnetic field lines for a bar magnet?

  • Draw the magnetic field lines around the magnet
  • Label areas where the field is strongest
  • Use arrows to indicate direction
  • Ensure lines are denser near the poles
• How many marks are given for labeling areas of strong magnetic fields?

  3 marks