Paper 1 - 2a Electrical Circuits and Static Electricity Flashcards
Draw the circuit symbol for a lamp
an X in a circle
Draw the circuit symbol for a diode
An arrow head in a circle
Draw the circuit symbol for a resistor
A rectangular box
Draw the circuit symbol for a variable resistor
A rectangular box with a diagonal arrow
Draw the circuit symbol for an LED
Same as a diode with 2 arrows points away
Draw the circuit symbol for a fuse
A rectangular box with a horizontal one running through it
Draw the circuit symbol for a voltmeter
V in a circle
Draw the circuit symbol for an ammeter
A in a circle
Draw the circuit symbol for a thermistor
a rectangular box with a diagonal line through it
Draw the circuit symbol for an LDR
A rectangular box in a circular with 2 arrows pointing towards it
Which way does current flow in a circuit?
Positive to negative (anode to cathode)
Define current
Rate of flow of charge (electrons) measured in amps (A)
Define potential difference
work done / energy per unit charge (V = E/Q)
State the equation that links charge, current and time.
Charge = Current x time Q = It
What are the units of charge?
Coulombs (C)
What is the relationship between current and resistance?
As resistance increases, current decreases and vice versa
State the equation that links potential difference, current and resistance
Potential difference = current x resistance V = IR
State the units of potential difference
Volts (V)
State the units of resistance
Ohms (?)
State the relationship between the length of wire and its resistance.
As the length of the wire increases the resistance increases. They are directly proportional
As more resistors are added in series what happens to the total resistance?
Total resistance increases (Rt = R1 + R2 + …..)
State Ohm’s law
Current is directly proportional to potential difference constant temperature. this means resistance remains constant.
Sketch the I-V graph for a resistor
A straight line through the origin (current and potential difference are directly proportional - an ohmic conductor)