Question
Write the history of magnet in brief.

Answer

→We know that a magnet possesses the property of attracting iron.
→Magnetic phenomena are universal in nature. The earth's magnetism predates human evolution.
→The word magnet is derived from the name of an island in Greece called 'magnesia' where magnetic ore deposits were found, around 600 BC .
→Shepherds on this island complained that their wooden shoes (which had nails) at times stuck to the ground. This property of magnets made it difficult for them to move around.
→The directional property of magnets was also known since ancient times. A thin and long piece of a magnet, when suspended freely, points in the north-south direction.
→The name loadstone (OR lode stone) was given to a naturally occuring ore of iron-magnetite, which means leading stone.
→The very first use of magnet (OR magnetic needles) was done by the Chinese for navigation on ships.
→Caravans crossing the Gobi Desert also employed magnetic needles.
→About four thousand years ago, an emperor Huang-ti got built a chariot by his craftsmen ('engineers' of today) on which they placed a magnetic figure with arms out stretched.
Image
→The figure swiveled around so that the figure of the statuette on it always pointed south. With this chariot, Huang-ti's troops were able to attack the army of enemy from the rear in thick fog, and were able to defeat them.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

(a) An electrostatic field line is a continuous curve. ie., a field line cannot have sudden breaks. Why not?
(b) Explain why two field lines never cross each other at any point.
A spectroscopic instrument can resolve two nearby wavelengths $\lambda$ and $\lambda+\Delta\lambda$ if $\frac{\lambda}{\Delta\lambda}$ is smaller than 8000. This is used to study the spectral lines of the Balmer series of hydrogen. Approximately how many lines will be resolved by the instrument?
Explain physical meaning of electric field.
The angles of dip at two places located on the earth are 0° and 90° respectively. Where are the places located?
An unruly demonstrator lifts a stone of mass 200g from the ground and throws it at his opponent. At the time of projection, the stone is 150cm above the ground and has a speed of 3.00m/s. Calculate the work done by the demonstrator during the process. If it takes one second for the demonstrator to lift the stone and throw, what horsepower does he use?
Obtain the equivalent focal length of combination of thin lenses placed in cantact.
$\left(\frac{1}{f}=\frac{1}{f_1}+\frac{1}{f_2}\right)$
The susceptibility of a magnetic material is –2.6 × 10–5. Identify the type of magnetic material and state its two properties.
A thin spherical shell of radius R lying on a rough horizontal surface is hit sharply and horizontally by a cue. Where should it be hit so that the shell does not slip on the surface?
Obtain the equation of electric energy of a single (solo) charge.