Curie Law - DIY kit for Students

CONCEPT:

Curie Law:- The principle that the magnetic susceptibility of a paramagnetic substance is inversely proportional to the difference between its temperature and its Curie point. The temperature beyond that at which a ferromagneti c substance exhibits paramagnetic, also called Curie temperature. INTRODUCTION: Friends you might have heard that a magnet looses its property of attraction when heated.Similarly when a metal wire also when heated a tcert a in temperature it looses its property of attraction to wards magnet. So let's understand this by carry in gout an activity.

MATERIAL: Plastic base D-size battery socket-2 Thread piece

Steel rod

Magnetic ring

Wire -3 Square PVC pipe

D-size battery -2 (not in cluded in the kit) THINGS YOU NEED: SCREW DRIVER-1 Ni chrome wire

L Bracket-2 Sleeve

Bolt-1 Nut-bolt-4

Observation:

As soon as we touched the wires with the Ni chrome,you will notice that wire gets heated up and becomesred. Then you will notice that the magnet gets detached and hangs due to gravity.Now take away both the wire and let the Ni chrome wire gets cool down. When the wireis cooled,you will notice that the magnet will stick to it once again.

Why:

This happens because Ni chrome is a ferromagnetic material.The ferromagnetic material has the property have a specific property to get attracted towards the permanent magnet due to temporary magnetization generated within in them by the presence of other magnet. Fe, Ni,and Co is ferromagneti c. Here the Ni chrome wire attracts the magnet because it consists of Nickel. In ferromagnetic substance the magnetic do mainare aligned in one direction.The high temperature disturbs the alignment of domain in one direction and hence it looses its magnetism. The temperature at which the ferromagneti c substance looses its property of attraction towards magnet is called Curie temperature, as this fact was given by the Scientist Pierre Curie. Hence as the Ni chrome wire becomes hot it looses ferromagnetism and permanent magnet looses attraction and hence the ring magnet behaves as ordinary pendulum.

ADDITIONAL INFORMATION:­

Magnetite is a natural magnet.

Magnet attracts materials like iron,nickel,cobalt.These are called magnetic materials. Each magne tha s two magnetic poles-Nort hand South.

A freely suspended magnetalways aligns in N-S direction.

Opposite poles of two magnets attrac teach other where assimilar poles repelone another.