# Measuring voltage current and resistance relationship

### Voltage, Current and Resistance | HowStuffWorks

Voltage, Current and Resistance - To find out more information about electricity and pushing the electrons along is called the voltage and is measured in volts. calculator equation power law current charge resistance converter ohm's law The SI unit of measurement of electric voltage, the volt, was named after him. 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.

If you plug in a light and it draws half an amp, it's a watt light bulb. Let's say that you turn on the space heater and then look at the power meter outside.

The meter's purpose is to measure the amount of electricity flowing into your house so that the power company can bill you for it.

### Relationship and Difference Between Voltage, Current and Resistance

Let's assume -- we know it's unlikely -- that nothing else in the house is on, so the meter is measuring only the electricity used by the space heater. Your space heater is using 1.

If you leave the space heater on for one hour, you will use 1. If your power company charges you 10 cents per kilowatt-hour, then the power company will charge you 12 cents for every hour that you leave your space heater on. Now let's add one more factor to current and voltage: We can extend the water analogy to understand resistance, too. The voltage is equivalent to the water pressure, the current is equivalent to the flow rate and the resistance is like the pipe size.

A basic electrical engineering equation called Ohm's law spells out how the three terms relate.

• Ohm’s Law - How Voltage, Current, and Resistance Relate
• Current, voltage and resistance

Current is equal to the voltage divided by the resistance. It's written like this: Let's say you have a tank of pressurized water connected to a hose that you're using to water the garden.

## How Electricity Works

If you increase the pressure in the tank, more water comes out of the hose, right? The same is true of an electrical system: Increasing the voltage will result in greater current flow. Now say you increase the diameter of the hose and all of the tank's fittings.

This adjustment would also make more water come out of the hose. Voltage is a specific measure of potential energy that is always relative between two points. When we speak of a certain amount of voltage being present in a circuit, we are referring to the measurement of how much potential energy exists to move electrons from one particular point in that circuit to another particular point.

Free electrons tend to move through conductors with some degree of friction, or opposition to motion.

## Relationship and Difference Between Voltage, Current and Resistance

This opposition to motion is more properly called resistance. The amount of current in a circuit depends on the amount of voltage available to motivate the electrons, and also the amount of resistance in the circuit to oppose electron flow.

Just like voltage, resistance is a quantity relative between two points. Volt, Amp, and Ohm To be able to make meaningful statements about these quantities in circuits, we need to be able to describe their quantities in the same way that we might quantify mass, temperature, volume, length, or any other kind of physical quantity.

Here are the standard units of measurement for electrical current, voltage, and resistance: Standardized letters like these are common in the disciplines of physics and engineering, and are internationally recognized. Each unit of measurement is named after a famous experimenter in electricity: The amp after the Frenchman Andre M.

The mathematical symbol for each quantity is meaningful as well. Most direct-current DC measurements, however, being stable over time, will be symbolized with capital letters.

Voltage, Current and Resistance

Coulomb and Electric Charge One foundational unit of electrical measurement, often taught in the beginnings of electronics courses but used infrequently afterwards, is the unit of the coulomb, which is a measure of electric charge proportional to the number of electrons in an imbalanced state. One coulomb of charge is equal to 6,,, electrons. Cast in these terms, current is the rate of electric charge motion through a conductor.