Physics unit 1 Flashcards
In which direction does a magnetic field move?
Always from North to South
how does a battery make electricity flow
it acts like a pump and provides the force to push the charge around
what is current
the flow of charge around a circuit
what instrument is used to measure current
an ammeter
what is not used up in a circuit
current
what is a series circuit
a circuit that is connected in one continuous loop
what is a parallel circuit
at some point the circuit splits into 2 branches and the current is split between them before rejoining later
what is electrical current
the rate of flow of charge
what is voltage
a measure of the energy being carried by electric charges (in a circuit)
in a series circuit the current is …
the same
in a series circuit the voltage is …
split between components
in a parallel circuit the current is …
split
in a parallel circuit the voltage is …
equal on each branch
what is resistance
a measure of how well a component opposes current.
the higher the resistance…
the lower the current
what is the equation to calculate resistance
resistance = voltage
______
current
what is resistance measured in
Ohms
what is the equation for the total resistance in a series circuit
total resistance = R1 + R2 + R3 …..
what is the equation for the total resistance in a parallel circuit
total resistance = 1 + 1 + ….
—– —–
R1 R2
what is an LDR
light dependent resistor
what does an LDR do
it changes resistance with light
what is a thermistor / Ntc (negative temperature co - efficient)
a heat dependent resistor that changes resistance with heat levels. the higher the temperature the lower the resistance