Potential Dividers in Sensor Circuits Flashcards
In a series circuit what happens to the current?
It is the same everywhere
What is a potential divider circuit?
A circuit where the applied potential difference is spit up between the components
What happens to the potential difference in a sensor circuit?
It is shared across the components
What happens to the resistance in a sensor circuit?
It adds up
What does V1 / V2 equal?
R1 / R2
For a potential divider, as V1 / V equals R1 / R total, what does V1 therefore equal?
V1 = V X R1 / R total
What is a fixed resistor?
A resistor where the resistance remains fixed
What is a variable resistor?
A resistor where the value of the resistance changes
Give two examples of variable resistors:
-Thermistor and LDR (light dependant resistor)
What happens to the resistance of a thermistor as the temperature increases?
The resistance decreases
Why does the resistance across a thermistor decrease when the temperature increases?
An increase in temperature liberates electrons, causing the conductivity to increase, so the resistance decreases
What happens to the resistance of a light-dependant resistor as the light intensity increases?
Electrons are liberated, which increases the conductivity, resulting in a drop in the resistance
