Unit 10 - Electrical Circuits Flashcards
What is Kirchhoff’s second law?
In any circuit, the sum of the electromotive forces is equal to the sum of the potential differences around a closed loop.
What does internal resistance mean?
the opposition to the flow of current offered by the cells and batteries themselves resulting in the generation of heat.
What is a potential divider circuit?
A simple circuit that uses resistors (or thermistors / LDR’s) to supply a variable output potential difference.
What equation is used to work out the output voltage across a resistor.
Vout = (R2/R1+R2)x Vin
What is a sensing circuit?
It is a type of potential divider circuit that uses a thermistor, variable resistor or an LDR rather that a fixed resistor.
What is a potentiometer?
works in the same way as a potential divider but rather than using two resistors in series it uses a length of resistance wire with a sliding contact.
