Core Concepts Flashcards
What is current?
Flow of electrons around a circuit.
How is the current flowing in a circuit?
It is the same at all points.
What is current measured in and what is its symbol?
Measured in Amps.
Symbol is “I”.
What is voltage?
The force that pushes the current around the circuit.
What happens if the voltage is large/small?
If it is large then the current will be large.
If it is small then the current will be small.
What is voltage measured in and what is its symbol?
Measured in Volts
Symbol is “V”.
What is resistance?
The restriction of the flow in a circuit.
What happens when the resistance is large/small?
If it is large then the less current will flow.
If it is small then the more current will flow.
What is resistance. measured in and what is its symbol?
Measured in Ohms.
Symbol is “R”.
What is Ohm’s law?
V = IR
What is Kirchhoff’s voltage law?
The sum of the voltage in a circuit is equal to the supply voltage:
V0 = V1 + V2 + V3
What is Kirchhoff’s current law?
The sum of the currents entering a point in a circuit, are equal to the sum of the currents leaving that point:
I1 + I2 = I3 + I4
What is the Potential Divider equation?
Vout = Vin(R2/R1 + R2)
When can a LDR be seen as a closed switch?
When the light level increases.
When can a LDR be seen as a open switch?
When the light level decreases.
