by using compass.
compass
You can detect it by watching a compass needle, if that's what you mean.
A magnetic needle meter, or a simple compass.
You don't but your compass does: it's the Earth's own magnetic field's polarity and direction.
A plotting compass is used to detect which direction the North Pole is located. You can stand in any position and it will always point north. +++ That's a navigation compass. A plotting compass will indeed point to the Earth's Magnetic North Pole (not the axis pole), if not influenced by any other magnet; but its purpose is in plotting the magnetic field around a magnet.
You can detect the magnetic field by its pull on another magnet, including a compass needle.
A compass needle is actually a weak magnet. Because in magnetism opposite polarities attract while like polarities repel, the needle's north pole seeks the earth's south pole and vice versa.
You can detect the presence of a magnetic field using a compass, which will align itself with the field lines. Other devices such as magnetometers can also detect and measure magnetic fields accurately. Additionally, certain materials, such as iron filings, can visualize magnetic field patterns when sprinkled around the area.
sneakoscope is a small toy looking object it is use to detect dark magic. its like a compass it spins when the dark magic comes near.
It's a dipping needle mining compass from around 1900. It was used to detect areas of magnetism, which might indicate gold, since gold is often found with magnetite black sand.
No,a Gyrosyn compass is a combination of a Magnetic compass and Direct reading compass.