P4 Flashcards
How can we calculate energy transferred using potential difference and charge?
E =Q V
Define resistance
The opposition to current flow
What is Ohm’s law?
At a constant temperature, current through a component is proportional to potential difference
Why is a filament lamp a non-Ohmic component?
The resistance increases as the current increases, due to its increase in temperature, so the current is not directly proportional to the potential difference
What will happen to the resistance of a thermistor as the temperature increases?
The resistance will decrease
What happens to the resistance of an LDR as light gets brighter?
It decreases
How are components connected in series?
One after the other- if there is a break anywhere, charge will stop flowing
What is the total resistance of a series circuit?
The total of the resistance of each component
In a series circuit, will a component with higher resistance have a greater or smaller share of the potential difference?
Greater
What does a variable resistor do?
Changes the resistance to keep the current constant
