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(ii) Magnet can be demagnetised by placing it within a solenoid and passing high frequency AC
through it.
Extra Information:

USES OF MAGNETISM IN MEDICINE:

An electric current always produces a magnetic field. Even weak ion currents that travel along the

nerve cells in our body produce magnetic fields.
When we touch something, our nerves carry an electric impulse to the muscles we need to use. The

impulse produces a temporary magnetic field. These fields are very weak and are one billionth of
the earth's magnetic field. Heart and brain are the two main organs in the human body where the

magnetic field produced is significant. The magnetic field inside the body forms the base of
obtaining the images of different body parts. This is done by using a technique called Magnetic

Resonance Images (MRI). Analysis of these images helps in medical diagnosis. Magnetism has
thus, got important uses in medicine.