Who has first used the properties of showing the direction of the magnet and why ?
Who has first used the properties of showing the direction of the magnet and why ?
A thin long piece of a magnet when suspended freely, pointed in the north-south direction.
When it was placed on a piece of cork which was then allowed to float in still water. It is shows also north-south direction.
The name lodestone (or loadstone) given to a naturally occurring ore of iron magnetite means leading stone.
The first use of magnet was made by the Chinese people to determine the direction while traveling in the sea.
Caravans crossing the Gobi desert also employed magnetic needles.
A Chinese legend narrates the tale of the victory of the emperor Huang-ti about four thousand years ago, which he owed to his craftsmen (engineers).
These engineers built a chariot on which they placed a magnetic figure with arms outstretched. The figure swiveled around so that the finger of the statuette on it always pointed south. With this chariot, Huang-ti's troops were able to attack the enemy from the rear in thick fog and to defeat them.
Similar Questions
The magnetic field to a small magnetic dipole of magnetic moment $M$, at distance $ r$ from the centre on the equatorial line is given by (in $M.K.S. $ system)
The magnetic field to a small magnetic dipole of magnetic moment $M$, at distance $ r$ from the centre on the equatorial line is given by (in $M.K.S. $ system)
The small magnets each of magnetic moment $10 \,A-m^2$ are placed end-on position $0.1\,m$ apart from their centres. The force acting between them is....$N$
The small magnets each of magnetic moment $10 \,A-m^2$ are placed end-on position $0.1\,m$ apart from their centres. The force acting between them is....$N$
Assertion : The poles of magnet can not be separated by breaking into two pieces.
Reason : The magnetic moment will be reduced to half when a magnet is broken into two equal pieces.
Assertion : The poles of magnet can not be separated by breaking into two pieces.
Reason : The magnetic moment will be reduced to half when a magnet is broken into two equal pieces.
- [AIIMS 2017]
The magnetic moment of a magnet of length $10\, cm$ and pole strength $ 4.0\, Am$ will be......$A{m^2}$
The magnetic moment of a magnet of length $10\, cm$ and pole strength $ 4.0\, Am$ will be......$A{m^2}$
The mid points of two small magnetic dipoles of length $d$ in end-on positions, are separated by a distance $x, (x > > d)$. The force between them is proportional to $x^{-n}$ where $n$ is
The mid points of two small magnetic dipoles of length $d$ in end-on positions, are separated by a distance $x, (x > > d)$. The force between them is proportional to $x^{-n}$ where $n$ is
- [JEE MAIN 2014]