rp 3: resistance

• equation used to calculate resistance in a circuit

  resistance = potential difference / current
• what is zero error?

  • reading on a measuring instrument when the value should be zero
  • it is a systematic error
• 1. use the potential difference & current values to calculate the resistance
  2. to see how resistance changes with the length of the wire, use the crocodile clips to change the length of the wire

  
• how to reduce heating of the wire:

  • use a low potential difference, which will keep the current low
  • turn off the current between readings