AS Physics Unit 1.12 Potential Divider Circuits Flashcards
1
Q
What is a potential divider?
A
A potential divider is an arrangement of resistors which allows a fraction of the potential difference supplied to it to be passed on to an external circuit.
2
Q
How would you work out current in R1 in this circuit?
A
I = Vin / (R1 + R2)
3
Q
How would you work out the output voltage across R1?
A
The output voltage is the potential difference across R1, so:
Vout = I x R1
4
Q
How would you work out the voltage in this circuit?
A
Vout = (R1 x Vin) / (R1 + R2)
5
Q
What does the circuit not allow the user to do if the resistors are fixed?
A
It does not permit the user to vary the voltage across the load. In order to do that the fixed resistors must be replaced by a continuously variable resistor called a rheostat.
