potential difference dividers

• Potential dividers can be used to supply constant or variable potential differences from a power supply.
• • Often in electronics, the power supply has a potential difference that is too high for our intended use. 
  • Another problem is that we might want a variable potential difference when we only have a constant potential difference power supply.
  • A potential divider circuit uses the resistance of a resistor to change the potential difference across a component.
  • When the second resistor has a high resistance, there is a reduction of the potential difference across the component.
• • If a variable resistor is now in place of R1, the potential difference across the component can be altered.
  • When the variable resistor is set to zero, the component gets the full power supply of potential difference.
  • When the variable resistor is set higher, the component gets a smaller share of the full power supply of potential difference.
  • The potential difference can be altered to vary the potential difference with time or set it at a lower value than the power supply.
• • If a thermistor is now in place of R1, the potential difference across the component is altered based on the temperature of the thermistor.
  • When the temperature is high, the thermistor resistance is close to zero and so the component gets nearly the full power supply of potential difference.
  • When the temperature is low, the component gets a smaller share of the full power supply of potential difference.
• • If a light dependent resistor (LDR) is now in place of R1, the potential difference across the component is altered based on the light intensity incident on the LDR.
  • When the intensity is high, the LDR resistance is close to zero and so the component gets nearly the full power supply of potential difference.
  • When the intensity is low, the component gets a smaller share of the full power supply of potential difference.
• If we increase the resistance of a variable component, the potential divider will have less potential difference across it.
• A potential divider is used to either vary the potential difference across a component or to reduce the reduce the potential difference a component receives from the cell
• If we increase the resistance of a variable component, the potential divider will have less potential difference across it.
• if the light intensity is high the resistance of an LDR is low
• if a variable resistor is high the potential difference across it is large
• if the temperature is high the resistance of a thermistor is low