Thank You. I needed information like this.Mindscrape said:Voltage = potential difference between two points
Current = rate of change of charge with time
Resistance = proportional to the voltage and inversely proportional to current
Internal Resistance = Thevenin resistance seen by outside source
Thats a very good analogy. Thanks.Agnostic said:Think of it analogous to water flowing from an elevated tank through a small hose.
Voltage is the pressure behind the water which corresponds to amount of water in the tank pushing down.
Current is the speed of the water.
Resistance is something in the hose obstructing the path of water flow.
Internal resistance is the resistance of the water having friction with pipe walls.
Well, if you have a given EMF, generated by a magnetic field changing in time, and are near some circuit or wire, you can just use good ol' ohms law to find the resistance:Anived said:What is Internal Resistance in relation to EMF?
The Voltage that is lost in the Power supply.NoTime said:What do you mean by internal resistance?
Do you disagree with Mindscrape's definition?
E=IR
Does this affect the circuit in any way?NoTime said:Usually, for most things, it's negligable.
For actively regulated power supplys it can be 0 or even negative.
If it is a factor, then the power supply resistance gets added to the rest of the resistance in the circuit.
Yes, in exactly the same way a normal resistor would. Suppose you have a cell with a 12V emf and 1[itex]\Omega[/itex] internal resistance. This would be equivalent to a circuit containing a 12V cell with no internal resistance, in series with a 1[itex]\Omega[/itex] resistor.Does this affect the circuit in any way?
I see.Hootenanny said:Yes, in exactly the same way a normal resistor would. Suppose you have a cell with a 12V emf and 1[itex]\Omega[/itex] internal resistance. This would be equivalent to a circuit containing a 12V cell with no internal resistance, in series with a 1[itex]\Omega[/itex] resistor.
Resistors dissipate energy, how do you suggest they do this?I see.
Is it dangerous if the resistance gets high? If so why and what happens?
Resistance serves to limit the amount of Current through the circuit with a given amount of Voltage supplied by the battery.Hootenanny said:Resistors dissipate energy, how do you suggest they do this?
Yes, it does this by dissipating (removing) energy (from the circuit). This energy is dissipated as heat. Therefore, if you have a high resistance together with a high current flow, then large amounts of heat will be dissipated.Resistance serves to limit the amount of Current through the circuit with a given amount of Voltage supplied by the battery.
After lots of heat is dissipated, does the Resistance, Voltage or Current change (i.e go lower or higher)?Yes, it does this by dissipating (removing) energy (from the circuit). This energy is dissipated as heat. Therefore, if you have a high resistance together with a high current flow, then large amounts of heat will be dissipated.