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Can I have some information about these topics?
Thank You in Advance.
- Voltage
- Current
- Resistance
- Internal Resistance
Thank You in Advance.
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
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.
Anived said:What is Internal Resistance in relation to EMF?
NoTime said:What do you mean by internal resistance?
Do you disagree with Mindscrape's definition?
E=IR
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.Anived said:Does this affect the circuit in any way?
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.
Anived said:I see.
Is it dangerous if the resistance gets high? If so why and what happens?
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.Anived said:Resistance serves to limit the amount of Current through the circuit with a given amount of Voltage supplied by the battery.
Hootenanny said: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.
Some materials are superconductors, i.e. at low temperature have a zero resistance, if that is what you mean.Anived said:Is it possible to have an electrical product that has Zero Internal Resistance?
Hootenanny said:Some materials are superconductors, i.e. at low temperature have a zero resistance, if that is what you mean.
Voltage is a measure of the electrical potential difference between two points in a circuit. It is commonly referred to as "electrical pressure" and is measured in volts (V).
Current is the flow of electric charge through a conductor. It is measured in amperes (A) and is commonly represented by the symbol "I" in equations.
Resistance is the opposition to the flow of electric current. It is measured in ohms (Ω) and is represented by the symbol "R" in equations. Resistance is affected by factors such as the material of the conductor, its length, and its cross-sectional area.
According to Ohm's Law, voltage (V) is equal to the current (I) multiplied by the resistance (R) in a circuit: V = IR. This means that as voltage increases, current increases, and as resistance increases, current decreases.
Voltage can be measured using a voltmeter, current can be measured using an ammeter, and resistance can be measured using an ohmmeter. These devices are typically found in a multimeter, which can measure all three quantities.