ELECTRICAL CIRCUITS
Electrical circuits? How do they work then? Witchcraft? Voodoo? What is current? How is it different to voltage? Find out here as you indulge in this wonderful circuit builder made by those wonderful people at Phet! Absolute physics legends. Suggestions for investigations can be seen below in the embedded power point presentation! Let us know what you think or these - are they useful? Would you like to see more or less of them? Contact us via our contact page.
INVESTIGATIONS!
CURRENT AFFAIRS...
So what actually is electric current? We know it is measured in amps but what does it actually mean? Officially, its the rate of flow of charge. The video below explains, welcome to the weird world of charge, current and coulombs! Finally learn what is meant by Q = I x t and how to use this equation.
KEY CHARGE POINTS
Charge is a property of matter
Charge can be positive (+) or negative (-).
Charge is measured in Coulomb C.
In a circuit, negative charge (electrons) moves from one point to another.
Current tells us how fast the charge moves.
The formula for charge is:
Q=I x t
where Q is charge, I is current, and t is time
Potential Difference
So we all know the the current it the rate of low of charge around the circuit. But what about potential difference? This is the posh name for voltage. It tells us how many joules of energy are transferred per coulomb of charge. But what does it actually mean? Find out here.
POTENTIAL POINTS OF INTEREST
Potential difference is a measure of energy, per unit of charge, transferred between two points in a circuit.
Potential difference is also known as voltage and is measured in volts (V).
The formula for potential difference is:
V= E / Q
where V is potential difference, E is energy, and Q is charge.
The formula for potential difference can also be written as
V=I x R
where V is potential difference, I is current, and R is resistance.
Potential difference can be measured by a voltmeter, which is connected in parallel with the component