Static Electricity

• What is static electricity?

  Build-up of charge on insulating materials
• What causes sparks in static electricity?

  Discharge of built-up charge
• What do all materials contain?

  Positive protons and negative electrons
• Why are most materials neutral overall?

  Positive and negative charges cancel each other out
• What happens when materials are rubbed together?

  Electrons are transferred between them
• What occurs in conducting materials when rubbed?

  Electrons flow back, no charge builds up
• What happens in insulating materials when rubbed?

  Electrons can't flow back, charge builds up
• What charge does a polythene rod gain when rubbed with cloth?

  Negative static charge
• What charge does cloth gain when rubbed with a polythene rod?

  Positive static charge
• How does the transfer of electrons depend on materials?

  It varies based on specific materials involved
• What happens when an acetate rod is rubbed with cloth?

  Electrons transfer from acetate to cloth
• What causes positive static charges?

  Loss of negative electrons from an object
• What develops as an object gains more negative electrons?

  A potential difference between the object and earth
• What happens if the potential difference is large enough?

  Electrons can jump across the gap, causing a spark
• What is the potential of earth objects?

  Always at zero volts
• Can charges build up on conductors?

  Yes, but it's less common
• How can cars build up charge?

  Metal frame contacts wind, transferring electrons
• What happens when you touch a charged car?

  You may experience a small electric shock
• What is a spark in static electricity?

  Jumping of electrons across a gap
• What is the process of static electricity generation?

  • Rubbing materials together
  • Transfer of electrons occurs
  • Insulating materials retain charge
  • Conductors allow electrons to flow back
• What are the key differences between conductors and insulators regarding static electricity?

  Conductors:

  • Electrons can move freely
  • Charge does not build up

  
  

  Insulators:

  • Electrons cannot move freely
  • Charge builds up due to friction