What is electrical current?
Flow of electrical charge
The size of electric current is also the rate of …
Electrical charge
In a closed loop what is the value of the current
Always the same
What is alternating current?
When the electric current is constantly changing between positive and negative
What is direct current
When the electrical charge is always flowing in the same direction
When do the resistance of components such as lamps, diodes, thermistors and LDR’s change?
When the current changes
When does the resistance of a thermistor decrease?what relationship does it have with temperature?
As the temperature increase, inverse proportion
What is the relationship between the resistance on an LDR and light intensity?
Inverse proportion
How do you calculate the total resistance in a series circuit?
R1+R2=R(total)
In series and parallel , the potential difference is —- between components and has the ——- current in each component.
Shared, same
Why does adding resistors to a parallel circuit reduce the overall resistance?
There are alternate routes in parallel circuits, to move past blockages (resistors) can go to other branches.
What is an ‘I-V characteristic’?
A graph which shows how current flowing through a component changes as the potential difference is increased
What is the purpose of a variable resistor?
To change the resistance of a circuit
What is a way of describing a graph where it is directly proportional but doesn’t pass through the origin?
Linear graph
What is ohms law
the current through a conductor is proportional to the voltage across the conductor
