Static & Charge & Circuits

• What is the charge of an electron?


  Negative
• What is the charge of a proton?


  Positive
• Why does a balloon stick to the wall?

  Because it gains negative charges due to static electricity
• What happens to the wall when a balloon sticks to it?


  The wall rearranges its charges, becoming positively charged
• What is static electricity (SE)?


  • Build up of charge on insulating materials
  • Sparks form when SE is discharged
  • Electrons change surfaces when 2 insulating materials are rubbed together
  • In metals, electrons return to their original surface
  • Only electrons are transferred between 2 insulating materials
  • A spark is caused by the jumping of electrons during static discharge
• What is the property of matter that allows charges to repel or attract?


  Charge
• What is the rate of flow of charge called?

  Current
• How is current measured?

  In Amps, using an Ammeter
• What is needed to make current flow in a circuit?

  A source of voltage
• What is a complete circuit?


  A circuit where current can flow continuously
• If 40 coulombs of charge flow in 10 seconds, what is the current?


  4 A
• If 6 amps flows for 10 seconds, how much charge flows?


  60 C
• What does the movement of a rope represent in a circuit analogy?

  • Represents the current
  • Demonstrates the flow of charge
• What do circuit components like lamps or variable resistors represent in a circuit analogy?


  • Represent the devices that use electrical energy
  • Show how current is utilized in a circuit
• What happens to the gold leaf in a Gold-leaf electroscope when it is negatively charged?


  The gold leaf repels
• What happens to the gold leaf in a Gold-leaf electroscope when it is neutrally charged?


  The gold leaf hangs down
• What is the relationship between charge, current, and time in a circuit?


  Current = Charge / Time
• What is the unit of charge?

  Coulombs
• What is the unit of time in the context of current?

  Seconds
• What is the unit of current?

  Amps
• If a current of 4 A flows for 10 seconds, how much charge is transferred?


  40 C
• If a current of 6 A flows for 10 seconds, how much charge is transferred?


  60 C
• How does static electricity differ from current electricity?


  Static electricity is a build-up of charge, while current electricity is the flow of charge
• What happens to electrons when two insulating materials are rubbed together?


  Electrons change surfaces
• What is the effect of rubbing metals together compared to insulating materials?


  In metals, electrons go straight back, while in insulating materials, only electrons are transferred
• What causes a spark during static discharge?


  The jumping of electrons causes a spark
• What is the role of the acetate rod and cloth in the static electricity example?


  The acetate rod loses electrons to the cloth, becoming positively charged
• What happens when the cloth loses electrons to the rod?


  The rod becomes negatively charged
• What is the significance of the gold-leaf electroscope in demonstrating static electricity?


  It shows how charge affects the movement of the gold leaf
• How does the charge of the gold leaf change when it is negatively charged?


  The gold leaf repels due to like charges
• What happens to the gold leaf when it is neutrally charged?


  The gold leaf hangs down
• What is the relationship between charge, current, and time in the formula?


  Current is directly proportional to charge and inversely proportional to time
• How can you calculate current if you know the charge and time?


  By using the formula: Current = Charge / Time
• How can you calculate charge if you know the current and time?


  By using the formula: Charge = Current × Time
• How can you calculate time if you know the charge and current?


  By using the formula: Time = Charge / Current
• What is the significance of the ammeter in measuring current?


  It measures the rate of flow of charge in Amps
• What is the significance of the voltmeter in measuring voltage?


  It measures the potential difference in Volts
• How does the concept of potential difference relate to current flow?


  Potential difference is necessary to drive current through a circuit
• What is the role of a variable resistor in a circuit?


  It allows for the adjustment of current flow
• How does a lamp function in a circuit?

  A lamp converts electrical energy into light energy