The simplest form of this equation is that if voltage is equal to 1 volt and resistance is equal to 1 ohm, there will be 1 amp of current. To get 2 amps of current, you can either increase the voltage to 2 volts or decrease the resistance to 0.
Or increase the voltage to 1. But, the takeaway is, in some situations you can change the voltage, in others, you can change the resistance.
In more uncommon cases, you can even change the current. The world is your oyster! But, typically you change the resistance to make whatever current you need. These are symbols only and have no bearing whatsoever on how a resistor looks in real life. Unfortunately, while there are only a few ways to represent resistors, actual resistors change a lot. They can be big and heavy or smaller than a grain of sand.
They can be a variety of colors, shapes, connection styles, without it having any effect on their resistance. That being said, those size differences can be very important in other ways. Before we get into that, here are a couple examples of different resistors.
It may seem strange that there are so many different types and sizes of resistors. Being able to select the resistance you want is hopefully pretty obvious. You can see that the space between common values is not even and you miss certain whole numbers, like 4, 5, 6, 7, 8, and 9.
If you now add a resistor in series into this circuit — the current of the circuit will be smaller. The current flowing in the circuit with a resistor is smaller than the current in the circuit without a resistor. If we increase the resistance of a circuit the equivalent current decreases ie the current flowing in the complete circuit will be decreased.
Case now add a resistor then the current flow and reach where there is resistor, I think that current before resistor is 4A, and after passing through resistor current should reduce. But according to law it is not correct because current is same in a circuit. Think of a hose with water flowing out of it. The current after a resistor is the exact same as it was before the resistor.
If you now add a resistor in series into this circuit — the current of the circuit will be smaller. So yes, the resistor does reduce the current. But the current flowing into the resistor is still the same as the current flowing out. Electric current is carried by charge carriers, which in solids are usually electrons.
If there is no resistance to flow, and a steady electric field, electrons accelerate as any mobile thing does when subject to a steady force. To divide voltage in half, all you must do is place any 2 resistors of equal value in series and then place a jumper wire in between the resistors.
The cases where using a higher value resistor will damage a circuit exist, but are a bit less usual than the cases where it may simply produce a weaker result than desired, or a different frequency response than desired. The power rating of a resistor is the specification given with a resistor that serves to tell the maximum amount of power that the resistor can withstand.
Overheating of Resistor This is due to the voltage attempting to force more current electrons through the resistor than it is designed to pass. The burning odor is the breaking down of the components of the resistor : the carbon, the clay binding agent and the color code pigment painted on the resistor.
Wattage refers to the maximum that a resistor can dissipate. So subbing a higher wattage for lower is perfectly fine without any changes. The wattage rating is not exceeded with an applied voltage less than about V, but usually normal resistors are rated at V. Voltage varies directly with current. An example would be a single resistor connected across a voltage source.
And, only in the case that the current through is fixed by the circuit will only the voltage across change when the resistance is changed. An example would be a single resistor connected across a current source. In summary, Ohm's law holds for resistors but one must apply it in conjunction with other circuit laws such as KVL and KCL to fully determine the resistor voltage and current. Ohm's law states that the current flowing through a conductor is directly proportional to the voltage applied across the conductor.
That means if you increase voltage the current will increase proportionally in the conductor. For example if you have a voltage of one volt across a conductor having a resistance of 1 ohm then the current flowing through the resistor will be 1 amp. If the voltage is increased to 2 volts then the current flowing through the resistor be 2 amps. For 3 volts 3 amps and so on. The basic thing in an electrical circuit is that voltage applied across a fixed circuit alone determines current flowing through the circuit.
If you increase voltage the current will increase. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How can a resistor affect current AND potential at the same time? Ask Question. Asked 6 years, 11 months ago.
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