7.1.1 Magnetic Fields

• What is a magnetic field?

  A region of magnetic force
• Magnetic fields extend from the North pole to the South pole.South
• Field lines are closer together in areas where the magnetic force is stronger.
• What type of fields are magnetic fields?

  Three-dimensional
• Compass needles align with the direction of the magnetic field
• Match the source of the magnetic field with its visualization method:

  Permanent magnet ↔️ Field line diagrams

  Electromagnet ↔️ Compass needles
• The two key properties of magnetic fields are direction and strength.
• What direction does a magnetic field extend from?

  North to South pole
• The strength of a magnetic field is represented by the density of its field lines
• Where is the strength of a magnetic field typically greatest?

  Near the poles
• Order the locations of a magnet from strongest to weakest field strength:

  1️⃣ Near poles

  2️⃣ Away from poles

  3️⃣ Center of magnet
• What are the three primary sources of magnetic fields?

  Permanent magnets, electromagnets, Earth's core
• Permanent magnets generate magnetic fields through the alignment of electron spins
• How can the strength of an electromagnet's magnetic field be adjusted?

  By changing the current
• What is the Earth's magnetic field generated by?

  Movement of molten iron
• The density of magnetic field lines represents the field's strength
• Magnetic fields originate from three primary sources: permanent magnets, electromagnets, and the Earth's core
• Match the source of the magnetic field with its mechanism:

  Permanent Magnets ↔️ Alignment of electron spins

  Electromagnets ↔️ Current flowing through coils

  Earth's Magnetic Field ↔️ Movement of molten iron
• The Earth's magnetic field is static and unchanging.

  False
• From which pole do magnetic field lines originate?

  North pole
• The density of magnetic field lines represents the field's strength
• To which pole do magnetic field lines return?

  South pole
• The magnetic field lines of a horseshoe magnet are densest between the poles
• What type of magnetic field does a straight current-carrying wire produce?

  Circular field
• A solenoid creates a stronger magnetic field inside compared to a straight wire.
• Match the magnetic field source with its characteristic:

  Permanent Magnets ↔️ Fixed field strength

  Electromagnets ↔️ Adjustable field strength