Electrostatic forces

• What is electric charge?


  Electric charge is a fundamental property of matter that causes it to experience a force in an electromagnetic field.
• How many types of electric charges are there?

  There are two types of electric charges: positive charge and negative charge.
• In what unit are electric charges measured?

  Electric charges are measured in coulombs (C).
• What is the smallest unit of charge?


  The smallest unit of charge is approximately $1.6 \times 10^{-19}$ C, which is the charge of an electron or proton.
• What happens to like charges when they are brought close together?


  Like charges repel each other.
• What happens to opposite charges when they are brought close together?


  Opposite charges attract each other.
• What are the key points about electric charge?

  • Electric charge is a fundamental property of matter.
  • There are two types: positive and negative.
  • Measured in coulombs (C).
  • Smallest unit is approximately $1.6 \times 10^{-19}$ C.
  • Like charges repel; opposite charges attract.
• What is Coulomb's Law?


  Coulomb's Law describes the force between two electrically charged particles.
• What does Coulomb's Law state about the force between charges?


  The force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
• What is the mathematical formula for Coulomb's Law?


  $F =$$k \frac{{q_1 q_2}}{{r^2}}$
• What does each variable in Coulomb's Law represent?


  F is the force (N), k is Coulomb's constant, q₁ and q₂ are the charges (C), and r is the distance (m).
• How does the force change as the charges increase?


  The force increases as the charges increase.
• How does the force change as the distance between charges increases?


  The force decreases as the distance increases.
• What are the key points of Coulomb's Law?


  • Force is directly proportional to the product of the charges.
  • Force is inversely proportional to the square of the distance.
  • Force can be attractive (opposite charges) or repulsive (like charges).
• What is the definition of attraction in electrostatics?


  Attraction occurs between opposite charges, causing particles to move towards each other.
• What is the definition of repulsion in electrostatics?


  Repulsion occurs between like charges, causing particles to move away from each other.
• What are the characteristics of attraction and repulsion between charges?

  • Attraction occurs between opposite charges (positive and negative).
  • Repulsion occurs between like charges (positive-positive or negative-negative).
  • Attraction pulls particles towards each other.
  • Repulsion pushes particles away from each other.
• What does Coulomb's Law state about the force between two charged particles?


  The force is inversely proportional to the square of the distance between them.
• What happens to the force between two charged particles if the distance is doubled?


  The force becomes 1/4 of what it was originally.
• Why does the force between charged particles decrease when the distance increases?


  Because the force is inversely proportional to the square of the distance.
• What are the two types of electrostatic forces between charged particles?


  • **Attraction**: Occurs between opposite charges (positive and negative).
  • **Repulsion**: Occurs between like charges (positive-positive or negative-negative).
• What type of charge interaction causes attraction between particles?


  Opposite charges attract each other.
• What is an example of attraction between charged particles?

  A proton (+) attracts an electron (-).
• What type of charge interaction causes repulsion between particles?


  Like charges repel each other.
• What is an example of repulsion between charged particles?


  Two electrons (-) repel each other.
• How do electrostatic forces act between charged particles?


  They act at a distance without physical contact needed.
• What role do electrostatic forces play in atomic and molecular structures?


  They are crucial for the stability and interactions of atoms and molecules.
• What is the definition of an electric field?


  An electric field is a region around a charged particle where it exerts a force on other charged particles.
• How are electric fields represented visually?


  Using field lines that indicate the direction of force on positive charges.
• What do electric field lines indicate about their direction around positive and negative charges?


  Lines point away from positive charges and towards negative charges.
• What does the density of electric field lines represent?


  The closer the lines, the stronger the electric field.
• How is the strength of an electric field (E) calculated?


  $E =$$\frac{F}{q}$, where F is the force on a test charge q.
• What is the unit of electric field strength?


  Newtons per Coulomb (N/C) or Volts per meter (V/m).
• What happens when multiple electric fields from different charges are present?


  They add up vectorially through the principle of superposition.
• What are some applications of electrostatic forces in technology and daily life?


  • **Photocopiers and laser printers**: Transfer toner to paper.
  • Air purifiers: Remove dust and pollutants.
  • Spray painting: Ensure even coating.
  • Static cling: Clothes sticking together.
  • Lightning rods: Protect buildings from lightning.
  • **Electrostatic discharge (ESD) protection**: Safeguard electronics.
  • **Capacitors**: Store electric charge.
  • **Van de Graaff generators**: Demonstrate electrostatics.
• Which device uses electrostatic attraction to transfer toner to paper?


  Photocopiers and laser printers.
• What is the function of an electrostatic precipitator?


  It removes dust and pollutants from the air using electrostatic forces.
• How do electrostatic sprayers ensure even coating of paint?


  They charge paint particles to enhance attraction to surfaces.
• What is the purpose of lightning rods?


  To provide a path for lightning's electric charge to protect buildings.
• What is the role of capacitors in electronic circuits?


  They store electric charge for later use.