Question

how do magnetic compasses assist sailors ar sea

Answer 1

A compass is useful navigational tool that relies on magnetism to work. While there are different types of compasses, early explorer’s relied on magnetic compasses in navigation. The earth’s surface is covered by an invisible magnetic field. The north and south poles are aligned with the earth’s axis. Therefore, magnetic objects, like the needle of a compass, will align itself along the north-south axis.1 Magnetic compasses evolved from using lodestones. Lodestone is a type of magnetic mineral called magnetite. At sea there were two ways of using a lodestone: The first was to hang it from a string, and allow it to turn and point north. The second was to float it on a piece of wood in a bowl of water, where it would drift towards the north. Using the bowl of water method was better for sailors, because holding a string steady on a moving ship could prove difficult at times. Many historians have traced these early compass-like devices to ancient China before 1040.2 As trade between Asia and Europe increased, European travelers most likely brought back using this concept back with them.3

Around the late 1200s to early 1300s, sailors started using a dry compass. This new advancement used a pivoting needle attached to a compass card in a wooden box. The direction points of the compass card looked like a rose. So navigators often refer to this type of compass as a “compass rose.”4 Over the next hundred years, navigators and sailors, such as Christopher Columbus, relied on the compass to help them sail to new parts of the globe.

I hope this will help you

Answer 2

Magnetic compasses and their use.

Explanation:

A magnetic compass relies on the Earth's magnetic field and is used to determine one's orientation as compared to the Earth's magnetic field.

It is always aligned with the Earth's magnetic fields and points towards the magnetic north of the planet.

Sailors are expert in the use of magnetic compasses, and by correlating a magnetic compasses' bearing to the magnetic declination in the area, they can accurately determine the geographical north pole and navigate accordingly.