Magnetic compass is an outstanding inventionancient Chinese thinkers. Naturally, these days the device is not used as often as in the past. However, it is sometimes difficult for tourists, pilots and sailors without it. What is a magnetic compass? What is the principle of the device? What are the features of its application? Let's get to this together.
The device, which is a prototype of the modernmagnetic compass, was developed in the III century BC. At this time, Chinese inventors managed to design a device that indicated the sides of the world. The ancient device consisted of a magnetite spoon, which on one side contained a convex spherical part, and on the other a thin stem. The element was placed on a polished copper plate with markings in the form of the sides of the light. Being in free rotation, the stem of the spoon always stopped, pointing to the south.
Apparently, the first magnetic compass hadprimitive structure. The device had a lot of flaws. Magnetite, from which a rotating spoon was made, was difficult to process. In turn, friction was created between the convex part of such a direction indicator and the surface of the marked plate. Therefore, the compass pointed to the south with significant errors.
The invention was thoroughly refined in XIcentury. A Chinese scientist named Shen Gua suggested using a magnetized needle as the sign of the sides of the world. The latter was freely fixed on a thin silk thread. The fact that the tip of the needle always points to the south, the thinker explained by the mismatch of magnetic and geographic meridians.
In the XIII century, the magnetic compass became widespreadEuropean seafarers. If at first the device consisted only of a magnetized needle that rotated suspended on a thread or floated in a vessel on a piece of wood, then later the structure was placed in a body covered with glass.
A huge contribution to the improvement of magneticThe compass was made by the Italian inventor Flavio Giulio. It was he who suggested placing a movable magnetic index in the middle of the round dial, which was divided into separate sectors, according to the sides of the world. Later, the compass needle was fixed on the gimbal suspension, which helped to obtain more accurate indicators during the rolling on the ships.
In the modern compass, the magnetic needleis fixed on the axis. Since the element is in free motion, it requires a choice of the control direction from which the movement to the target will be conducted. In a magnetic compass, this is a conditional line that connects the South and North Pole of the planet. If the instrument is held in a static position, the arrow will always stop parallel to the specified line. Deviations of the pointer can be observed only nearby magnets or metal objects.
In order to determine the exact exponents, the magneticThe arrow of the compass moves along the so-called card. The latter is a circular scale, which contains 360 divisions. Each of them corresponds to one degree. The count is from the zero value according to the clockwise movement. The pointer to the north corresponds to division 0about. The eastern direction is determined by the mark in90 °. South can be identified by a value of 180 °, and to the west indicates a division of 270 °. The presented values are called the basic compass points. It is for them to determine the sides of the world.
To determine the operability of the device,It is necessary to arrange the compass in the magnetic field of another object. It can be a piece of metal or a piece of a magnet. It is important that the compass needle initially lies parallel to the north-south axis line.
To check the device, you must put it onA flat surface, waiting for the stop of the direction indicator. Further, it is sufficient to bring to the compass an object with its own magnetic field. As soon as the arrow starts to rotate, you need to remove the thing. If the pointer then returns to its original position, then the compass is working properly.
How to use the compass?The magnetic field of the Earth allows you to find the right landmarks in any part of the world. In order not to get lost, it is enough to note for yourself the starting point at the beginning of the movement. It can be any landmark, for example, a settlement, road, river. From the starting point, you need to step back a few dozen steps in the right direction and turn around. Then it will remain to put the compass on a flat surface and rotate it so that the arrow lies parallel to the direction of north-south. As soon as this happens, you will see which degree on the scale of the device corresponds to the starting point, and which target course. These numbers need to be remembered, because they will become important if you have to move back along this conditional line.
There are a number of practical recommendations for using the compass:
So we found out what a magnetic compass is andhow to use the device correctly. To always find the right direction in an unfamiliar terrain, it is important to exercise regularly using such a device, train observation and visual memory.
Finally it is worth noting that today magneticfew people continue to use compasses. After all, such once-indispensable devices have been replaced by multifunctional GPS-navigators, which are much easier to master. However, not everyone can afford such expensive devices. At the same time, accumulators of electronic navigators are often discharged at the most inopportune moment. It is in such situations that an old good compass will come to the rescue, with the help of which you can find your way home.
