P3.2.4 - Graphs of p.d and current Flashcards
1
Q
What is the graph for a resistance wire or a resistor?
A
It is a linear circuit element so as you change the potential difference, the resistance does not change
2
Q
What is the graph for a lamp?
A
If the wires gets hot then the resistance varies and the graph is not a straight line. It is a non-linear circuit element
3
Q
What is Ohm’s Law?
A
Current is directly proportional to the potential difference if the temperature does not change
4
Q
What is a diode?
A
It is a component that only allows a current to flow one way
5
Q
What does an ammeter do?
A
It measures current in series with a component
6
Q
What does a voltmeter do?
A
It measures potential difference in parallel across a component
