Electromagnetic Effects

• Electromagnetic Induction: If a wire is passed across a magnetic field/changing magnetic field, a small EMF is induced and can be detected by a galvanometer.

  
• The direction of an induced EMF opposes the change causing it.
• An induced EMF can be increased by:

  • moving the wire faster
  • using a stronger magnet
  • Increasing length of wire in magnetic field, e.g. looping the wire through the field several times.

  
• The current and EMF direction can be reversed by:

  • moving the wire in the opposite direction
  • turning the magnet round so that the field direction is reversed

  
• Fleming’s right-hand rule gives the current direction

  
• How does an increase in normal force affect friction?

  Friction increases as normal force increases
• What keeps the International Space Station in orbit?

  Earth's gravitational force
• What is the relationship between the nitrogen (N) and magnesium (Mg) symbols in the image?

  • The nitrogen (N) symbol is pointing upwards
  • The magnesium (Mg) symbol is pointing downwards
  • This suggests some kind of interaction or relationship between the two elements
• What type of diagram or representation is shown in the image?

  • The image appears to be a simple diagram or schematic
  • It shows two symbols (N and Mg) with arrows pointing in opposite directions
  • This could represent some kind of physical or chemical process or interaction between the two elements
• What is the significance of gravitational force being a non-contact force?

  It allows attraction without physical interaction
• What is the charge of the particles represented by the blue arrows in the image?

  -q
• What do the blue arrows in the image represent?

  • The blue arrows represent the motion or direction of the negatively charged particles (-q)
• What occurs when charges are the same in electrostatic force?

  The force is repulsive when charges are the same.
• What is the charge of the particles represented by the blue arrows in the image?

  • The blue arrows represent particles with a charge of -q
• What do the blue arrows in the image represent?

  The motion or direction of the negatively charged particles
• How do non-contact forces differ from contact forces?

  Non-contact forces act without physical touch.
• In the provided image, what does the table represent in relation to the normal contact force?

  The table supports the weight by applying normal force
• What type of force is gravitational force?

  Non-contact force
• How does gravitational force act between objects?

  It pulls objects towards each other
• Can gravitational force act without physical contact?

  Yes, it acts without contact
• What is the charge of the particles represented by the yellow circles in the image?

  • The yellow circles represent particles with a charge of +q
• What are the key properties of magnetic fields?

  • Magnetic fields are invisible
  • Magnetic fields have a north and south pole
  • Magnetic fields exert forces on magnetic materials
  • Magnetic fields can be visualized using magnetic field lines
  • Magnetic fields can be created by electric currents
• What is the definition of electrostatic force?

  It is a non-contact force between charged objects.
• If the north pole of a magnet is placed near the south pole of another magnet, what will happen?

  The magnets will attract each other
• How can the direction of a magnetic field be reversed?

  • Reverse the direction of the electric current flowing through the wire/coil
  • Flip the north and south poles of the magnet
• How does magnetic force occur?

  Through interaction via a magnetic field
• What are the differences between permanent magnets and electromagnets?

  Permanent Magnets:

  • Produce a constant magnetic field
  • Cannot easily change the magnetic field strength

  
  

  Electromagnets:

  • Produce a magnetic field only when electric current is flowing
  • Can easily change the magnetic field strength by controlling the current
• How does magnetic force compare to gravitational and electrostatic forces?

  All can operate without direct contact
• What is the relationship between air resistance and an object's motion?

  Air resistance opposes the motion of the object
• What is the significance of magnetic force being a non-contact force?

  It allows interaction without physical touch