You might have gone for some exploration in mountains or forests and at that time your only friend has to be a magnetic compass. A magnetic compass has a magnetic needle that moves with the Earth’s magnetic field. You all know what is a magnetic compass but do you know how it works? A magnetic compass is used to find directions but how and why does a magnetic compass always show north? This is a very interesting question that we are going to answer here. Other than navigation, there are other different uses of a compass. Read this article to navigate through all your curiosities.
1. What is used to determine Direction?Image by Mario Aranda from Pixabay
The magnetic compass is used to find directions. The compass works in alignment with the magnetic field of the earth and helps navigate by pointing in the north direction. The compass has a magnetic needle or pointer that always points toward the north. So, it is a reliable and accurate form of navigation that is used by surveyors and sailors. (See 13 different types of compasses)
2. When was Compass first used?
Before understanding how is a magnetic compass used to find direction, let us see when it was first invented. According to historians, China may have been the first civilization to use a compass. Compasses were first used as early as the 11th or 12th century by Chinese scientists. It was used for navigation purposes. At the end of the 12th century, Western Europeans started using compasses as a backup when they could not see celestial bodies like the sun, moon, or stars to navigate.
But soon, compasses started to be used widely because they became more reliable and accurate. They turned into an important navigation tool. Other than finding the directions, there are some different uses of a compass which you will know further. Check out How can You differentiate between Map and Globe?
3. How is a Magnetic Compass used to find Direction?
The magnetic compass always points north, i.e., basically, the magnetic compass is used to find north. The needle of the magnetic compass always points in the north-south direction and helps determine the direction. The magnetic needle is able to rotate freely. The needle has a red arrow and the direction where it stays in the north direction. The remaining three directions can be found once knowing the north direction. The east direction lies to the right of the north, the west lies to the left whereas the south lies opposite to the north. Now you know how is a magnetic compass used to find direction. (See What is North South East West called on a Map?)
4. Magnetic Compass is used to find What?
The magnetic compass is used to find the directions. It is a scientific instrument built to determine directions on the surface of the Earth. It has a magnetic pointer that aligns itself with the Earth’s magnetic field and is one of the most used and reliable forms of the navigation device. It is used in many forms in ships, aircraft, and land vehicles. (See How to Identify North West East South?)
5. What are Different Uses of a Compass?Image by Ylanite Koppens from Pixabay
A compass is a very important device used to navigate ships. It is used by surveyors, mariners, sailors, etc., to find directions accurately. Even though one of the main purposes of a compass is to navigate, it is also used for other purposes. Some of the different uses of a compass are:
- To mark landmarks in building and construction,
- To measure horizontal and vertical lines for maps,
- To plot magnetic field lines, and
- To check the polarity of other magnets.
6. Why does a Magnetic Compass always show North?
Why does a magnetic compass always show north is indeed an interesting question to answer. The magnetic compass finds, points north, and helps us in determining the directions correctly. It always shows north because all magnets have two poles, the north, and the south pole. The earth’s magnetic field affects all magnetic objects, including the compass’s needle, and under its effect, the compass’s needle always shows north. (See How to find North Direction in Room?)
7. Can you use Magnetic Compass to find West Direction?
Yes, a magnetic compass is used to find directions and you can use it to find the west direction too. The magnetic compass aligns with the magnetic fields of the Earth and the needle or the pointer in the compass always points towards the north. West is to the left of the north and once you have determined the north, you can easily determine the west direction. (See In Which Direction does the Sunrise Occur?)
8. What is used to locate the East Direction?
A compass is used to locate the east direction. The magnetic needle in the compass points towards the north direction and the east is to the right of the north which can be easily located once the compass has determined the north direction. (See How to find House Facing Direction in Google Maps?)
9. Why does Earth have a Magnetic Field?By author MOHD AZRIN on Unsplash
It is still not clear why does Earth have a magnetic field, but there are a few theories about the same. The most common theory says that the magnetic fields are because of the earth’s core. The core of the earth is mainly made up of iron and nickel. The inner core has these metals in a solid state whereas the outer core has liquid metals which are in constant motion.
The rotation of the earth causes these metals to flow in spiral currents and this motion is responsible for the generation of the earth’s magnetic field. This principle is known as the dynamo effect. But this is just a theory and not a confirmation because the earth’s geomagnetic processes are still a mystery. (See What are the 5 Effects of Earth Rotation?)
10. Where is the True North?
True north is a fixed point on the Earth. It is the direction that points directly toward the geographic north pole. The magnetic north is not a fixed point as it works in alignment with the magnetic fields of the Earth. This point can change as the magnetic north changes and shifts over time. So, most of the compasses actually point in the direction of magnetic north and not towards the North Pole. True north can be found by adjusting the compass a few degrees. The changes in the degrees are due to the magnetic declination that varies from place to place. The true north can be found by using the Global Positioning System or GPS.
Now you know how is a magnetic compass used to find direction. And I hope you have the answer to the question- why does a magnetic compass always show north? This was a good take on one of the most basic things. Even you got to know the difference between magnetic north and true north, which is very interesting. This article would make you come back here for more! (See What is a depth measurement instrument?)