What is current, voltage and charge?Watch

#1
I'm doing IGCSE Physics this summer and I still don't understand the difference between current, voltage and charge. I mean, I know the differences in terms of equations, i.e:

voltage is the energy transferred per unit of charge passed - but what IS charge passed? In terms of electrons going around a circuit, what IS the charge? And how does that relate to voltage? And then current?

Also, for example, when a current is flowing through a circuit, is it the current, voltage or charge that makes the bulb light? And if there is resistance, does it stop the current, voltage or charge?

Thanks in advance for any help
0
7 years ago
#2
charge is like a packet of electrons, current is the flow of electrons / charge, voltage is the energy of the charge

V=IR
Q=It

All 3, the current or charge (pretty similar) need to have a voltage (energy) in order to light up the bulb.

And think of current/charge being drawn to the resistances in a circuit whereby voltage (energy) is dissipated by the current/charge that are carrying energy.

You may think now that why doesn't voltage from the battery decrease? Voltage is the energy per coulomb of charge not straight forwardly the energy in the circuit.

E=IVt
1
#3
(Original post by boboyt)
charge is like a packet of electrons, current is the flow of electrons / charge, voltage is the energy of the charge

V=IR
Q=It

All 3, the current or charge (pretty similar) need to have a voltage (energy) in order to light up the bulb.

And think of current/charge being drawn to the resistances in a circuit whereby voltage (energy) is dissipated by the current/charge that are carrying energy.

You may think now that why doesn't voltage from the battery decrease? Voltage is the energy per coulomb of charge not straight forwardly the energy in the circuit.

E=IVt
So is the charge the 'packets' of electrons moving around, the current the rate of flow of these packets, and the voltage the energy these packets have to give to components? And does higher resistance mean the same voltage but less current?

Thanks for the help
0
7 years ago
#4
Charge is the flow of electrons that move around. The direction of charge can be electron flow or conventional current. Current is the charge that flows in a certain amount of time. Voltage / Potential Difference is like the driving force by which electrons flow. e.g. More Voltage > More Current

Higher the resistance, the current will reduce because there is less charge, due to electrons finding it hard to move around. The voltage provides acceleration for the electrons (if you get what i mean).
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