Advice 1: How to determine the polarity of the magnet

Each magnet is required to have two poles, usually called North and South. If you have a magnet, the poles of which are unmarked, and determine its polarity is still needed(for example, if it is a part of the stator of the motor. This can be done by yourself without the help of instruments.
How to determine the polarity of the magnet
Instruction
1
The easiest way to determine the polarity of an unmarked magnet are marked. As a rule, the North pole of the magnet, note blue paint, southern, accordingly red. Since like poles repel each other and unlike attract each other, it is enough to see which pole of your magnet will be repelled from the North pole reference, to determine where, and what.
2
For the same purpose you can use the compass, which, in fact, represents a magnetic needle, freely rotating on the axis. Bring your magnet to the compass and see what it pole will attract the North end of the arrow. This will be the South pole of your magnet.
3
If you have no compass, you can make yourself, but this will require the ability to navigate the terrain. After the magnet a few times with an iron needle, you will magnetize it. Then lubricate the needle with any oil, put it on the water surface, poured into a saucer. If the saucer is wide enough, and not near strong magnets, the arrow will point one of its ends to the North. To determine where North is and where South is possible, for example, the sun in the Northern hemisphere it most of the year is moving along the South side of the sky. You can then check the polarity of your magnet the same way as with a conventional compass.
4
Force field lines enter the South pole of the magnet in and out of the North, as if revolving in a circle. Electric charge is caught in this field will follow the movement of lines.

Sprinkling some powdered sugar in a clean and dry plastic jar, close it and how to shake until the powder will not get electrified. exactly and don't start sticking to the walls of the jar. So you get positively-charged dust.

Put the magnet on the table so that its poles were in a horizontal position. Magnet from a speaker, for example, it will have to put on an edge. Then pour a little of the charged dust in the air above a magnet. Motes spun along the lines of.

Advice 2: How to determine the polarity dynamics

At first glance, the labeling on the speaker polarity has no meaning, since it is supplied to the AC voltage. But when the speaker system a few drivers, you must include them in phase. Denoted on the findings of the head of such polarity, in which the diffuser is moving forward.
How to determine the polarity dynamics
Instruction
1
Fabricate to check speakers special sampler. To do this, take an ordinary pocket lamp based on incandescent bulbs. Remove the switch and instead connect the two probes. They have to be isolated pens, as in the time of the off voltage at the terminals of the head there is a voltage of self-induction. Check the polarity of the voltage across the probes with a test voltmeter. Coat them with the appropriate designation. Make sure that if the probes are close, the light bulb glows.
2
Turn off the amplifier and all stereocomplex (including and from the socket). Disconnect both output drivers from other circuits to the speaker. Connect the probes to the terminals head without touching neither the last nor the metal parts of the probes. At this point, look carefully at the diffuser. If it moves outwards, and when you disable the interior, the polarity is correct. If the reverse is the case, change the polarity connection of the test leads, then repeat the test. Then mark on the frame the dynamic head of a black permanent marker polaritycorresponding to the polarity of the probes.
3
Carry out the same operation in relation to the other speakers within one speaker system. Regardless of how they are connected (directly or through crossover), connect them in-phase so that the red terminal on the rear of the column was consistent with the positive findings of the heads.
4
Also check and, if necessary, readjust the second speaker system. Closing the housing of both speakers, check that they are connected to the amplifier. On the cable, which is such a compound, there are special red labels. In all cases the conductor labeled connect to red terminal, and conductor no label - black.
5
Turn on stereocomplex. Compare its sound to that which occurred prior to alteration.
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