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What are the rules for current, voltage and resistance in series and parallel circuits? (Actually, I don't need to know the one for resistance in parallel.) I'm really struggling with physics :S
Any help is appreciated, thank you.
What are the rules for current, voltage and resistance in series and parallel circuits? (Actually, I don't need to know the one for resistance in parallel.) I'm really struggling with physics :S
Any help is appreciated, thank you.
A voltmeter, which measures voltage must always be connected in parellel to a component in a circuit eg in parellel to a variable resistor.
Ammeter which measures current must be connected in series in a circuit.
Current = the flow of electrons
Potential difference: The difference of electrical difference between two points in a circuit.
for simple series and parallel circuits you can use Ohm's Law:
V = IR
where
V is voltage or potential difference, measured in Volts (V)
I is current, measured in Amperes (A)
R is Resistance, measured in Ohms (Ω)
The rule for calculating total resistance is simple
In a SERIES circuit, you just add them up!
So R(total) = R(1) + R(2) + R(...)
For example the total resistance of a series circuit, R(total) with three resistors each of value 10Ω will be
R (total) = 10Ω + 10Ω + 10Ω = 30Ω
A PARALLEL circuit is more tricky:
1/R(total) = 1/R(1) + 1/R(2) + 1/R(...)
For example, the total resistance of a series circuit (Rtotal) with three resistors in parallel, each with a value of 10Ω will be
1/R(total) = 1/10Ω + 1/10Ω + 1/10Ω
so
1/R(total) = 0.3Ω
so
R(total) = 3.33Ω
You can see that in a parallel circuit the resistance is lower!
Using Ohms Law, you can now work out the current in each circuit. Say the circuit was powered by a 10V battery; so V = 10 V
SERIES
I = V/R = 10V/30Ω = 0.33A
PARALLEL
I = V/R = 10V/3.3Ω = 3A
So because the parallel circuit has a LOWER resistance, the current is HIGHER.
Try changing the values of the battery, V, and the values of the resistors, R
I just realised I forgot to thank you all~
A very belated thank you - the information was very helpful
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