What is the magnetic fixed and why does it matter?

This means that these three values ​​cannot be independent; If you know two of them, you can derive the third. How do physicists deal with this? We determine the speed of light as exactly 299,792,458 meters per second. (How do we know that it is accurate? Because we define a meter where the distance light travels at 1/299,792,458 a second.) Then we measure the magnetic fixed (μ₀) Use this value along with the speed of light for the electricity fixed account (ε₀).

It may seem to be deceived, but even starting actual science, at some point, we have to compensate for arbitrary units and identify some parameters. In fact, when you go down to it, all measurement systems are formed, just like all words.

The permeability of the free space

Magnetic fields (represented by the symbol forIt can be created by magnet, as shown at the top of the image. But because of this bond that we talked about, electric fees can also be made. (I use the summary term “fees” for charged particles, such as electrons)

You can see the magnetic fixed (μ₀) In there. We also have the value of the electric charge (S.) Move a certain speed (Fifth). So he says this magnetic field increases with the electric charge and decreases with the distance (PFrom the moving charge – and the magnetic steadfastness tells us how much it differs.

Of course, we do not deal with individual moving electrons often. But we are dealing with electrons transmission currents all the time: this is the electrical current, which we can measure. If we know the shipment on the particles in Coulombs, then the coupbs in the second gives us the current (I) In amperes. We can write the above equation in terms of current: B = μ₀I/(2πr).

It is everywhere

What tells us this is that The electrical current generates a magnetic field. This is used in all types of machines. For example, electromagnetic magnets give us, as magnetic force can be turned on and stopped to move metal objects in factories and jaw walls. It is also how the sound amplifiers create a sound: a magnetic driver electric signal, which generates pressure waves in the air.

also Magnetic fields affect electric currents. This is the way the engines operate. There is a stream that passes through a file of wires in the presence of a magnetic field that is usually created with some permanent magnet. The strength on the wire file causes it to rotate, and there is your engine. It can be a fan motor, part of the frequency current compressor, or the main drive of the electric car.

I am waiting! There is more. Just as the electric field creates a magnetic field change, A variable magnetic field creates an electric field– Which produces an electric current. This is how most of our strength is generated. Some power source – option, wind, moving water, whatever – connect the turbines that spin coils inside a magnetic field. The variable magnetic flow leads to an effort in the file, and turns mechanical energy into electrical energy that can be transmitted to your home.

Magnetic fixed measurement

How can we measure μ₀? One way uses the so -called current balance. A simple version of this has two parallel wires carrying electrical current (IIn two opposite directions, as shown in the graph below. Then you hang the wires with chains so that they can move, such as this:

The current in each wire creates a magnetic field at the location of the other wire, and this drives them away. While moving away, the magnetic force decreases and the horizontal component of tension increases in the support chain (due to the change in the corner). Once these two powers are equal, the wires will be “balanced”.

If you know the value of the electrical current and the distance between the wires (P), You can select the magnetic fixed, μ₀. After that, as we have shown above, you can use this value with the specific speed of light for the electricity fixed account, ε₀.

So, yes, everyone in all, you can say that the magnetic fixed is very important. Oh, and what is this fixed value? According to the International Committee for weights and measures, μ₀ = 1.256637061272 x 10^-6 us². No more, no less.