P4(Electric Circuits) Flashcards
What is static electricity
Friction between 2 insulators therefore transferring electrons from one insulator to the other insulator which causes one insulator to be positively charged and the other insulator to be negatively charged
What do like and unlike charges do
Like charges repel
Unlike charges attract
What is electric current
Rate of flow of charge
What is the formula that relates current, charge and time
Circuit symbols
What is potential difference
measure of how much energy is transferred between two points in a circuit.
What is the formula that relates potential difference, energy and charge
What is resistance
anything that stops the flow of current
What is the formula that relates resistance, potential difference and current
What is ohms law
the current is directly proportional to the potential difference provided the temperature and pressure are kept constant
What is the graph for a resistor
Potential difference is directly proportional to current which follows ohms law
What is the graph for a filament lamp
At start as voltage increases so does the current, current has heating effect, resistance increases and current levels off, doesn’t follow ohms law
What is the graph for a diode
Current through diode only flows if it is forward biased,current only flows if minimum voltage is 0.4 volts
What is the graph for a thermistor
Low temperature resistance is high, high temperature resistance is low
What is the graph for light dependent resister(LDR)
When it is Dark resistance is high, when it is Bright resistance is low
What is the formula for total resistance in a series circuit
What is the formula for total resistance in Parallel circuits
How do light sensors work
How do Thermostats work
What is the formula for potential dividers
