Ohm’s Law - How Voltage, Current, and Resistance Relate | Ohm's Law | Electronics Textbook
Electronics Tutorial about the Relationship between Voltage Current and Resistance in an Electrical Circuit and their relationship using Ohms Law. Did you know that electrical current is affected by the voltage and resistance in a circuit? In this lesson, we'll use Ohm's law, which tells us. This equation is based on the conservation of energy and conservation of charge . Calculating Resistance, Current, Voltage Drop, and Power Dissipation.
Thus, a 9 volt battery releases 9 joules of energy for every coulomb of electrons moved through a circuit. These units and symbols for electrical quantities will become very important to know as we begin to explore the relationships between them in circuits. Ohm expressed his discovery in the form of a simple equation, describing how voltage, current, and resistance interrelate: In this algebraic expression, voltage E is equal to current I multiplied by resistance R.
Using algebra techniques, we can manipulate this equation into two variations, solving for I and for R, respectively: In the above circuit, there is only one source of voltage the battery, on the left and only one source of resistance to current the lamp, on the right. In this first example, we will calculate the amount of current I in a circuit, given values of voltage E and resistance R: What is the amount of current I in this circuit? In this second example, we will calculate the amount of resistance R in a circuit, given values of voltage E and current I: What is the amount of resistance R offered by the lamp?
In the last example, we will calculate the amount of voltage supplied by a battery, given values of current I and resistance R: And it connects the ideas of voltage, which we will get more of a intuitive idea for in a second, and current, which is denoted by capital letter I, I guess to avoid confusion if they used a capital C with the coulomb. And what connects these two is the notion of resistance. Resistance, that is denoted with the capital letter R.
And just to cut to the chase, the relationship between these is a pretty simple mathematical one. It is that voltage is equal to current times resistance or another way to view it, if you divide both sides by resistance, you get that current is equal to voltage divided by resistance.
Voltage divided by resistance. But intuitively, what is voltage? And what is resistance? And what are the units for them so that we can make sense of this?
Introduction to circuits and Ohm's law
So to get an intuition for what these things are and how they relate, let's build a metaphor using the flow of water, which isn't a perfect metaphor, but it helps me at least understand the relationship between voltage, current, and resistance.
So let's say I have this vertical pipe of water, it's closed at the bottom right now, and it's all full of water. There's water above here as well. So the water in the pipe, so let's say the water right over here, it's gonna have some potential energy.The Basics of Voltage, Current and Resistance
And this potential energy, as we will see, it is analogous to voltage. Voltage is electric potential, electric potential. Now it isn't straight up potential energy, it's actually potential energy per unit charge. So let me write that. Potential energy per unit, unit charge.
You could think of it as joules, which is potential energy, or units of energy per coulomb. That is our unit charge. And the units for voltage in general is volts.
Now, let's think about what would happen if we now open the bottom of this pipe. So we open this up. Well, the water's immediately gonna drop straight down. That potential energy is gonna be converted to kinetic energy. And you could look at a certain part of the pipe right over here, right over here.
And you could say, well, how much water is flowing per unit time? And that amount of water that is flowing through the pipe at that point in a specific amount of time, that is analogous to current. Current is the amount of charge, so we could say charge per unit time.
Introduction to circuits and Ohm's law (video) | Khan Academy
Current is the flow of electrons Resistance is defined as, it is the tendency of a material to restrict the flow of current.
So, when we discuss about these values, the behavior of electrons in a closed loop circuit allows charge to move from one place to another. He described a unit of resistance which is defined by voltage and current. The difference between voltage and current and resistance is discussed below. In this equation, voltage is equal to the current and that is multiplied by resistance. Basic Circuit Diagram of V, I and R In the above circuit, when the voltage and resistance values are given, then we can calculate the amount of current.
The differences between V, I and R are discussed below. The voltage is defined as, it is the potential difference in charge between the two points on a circuit, it is also called electromotive force. One point has more charge than another. The unit volt is termed after invented by Italian physicist Alessandro Volta. The term volt is represented by the letter V in schematics.
- Relationship and Difference Between Voltage, Current and Resistance
- Ohm’s Law - How Voltage, Current, and Resistance Relate
The measuring instrument of voltage is the voltmeter. Voltage is the source and the current is its result, it can occur without current.
The voltage gets distributed over different electronic components which are connected in series in the circuit, and in parallel circuit voltage is same across all components which are connected in parallel. The current is defined as it is the rate of flow of electric charge in a circuit.