Name three liquids, which when tested in the manner shown in may cause the magnetic needle to deflect.

When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Can you explain the reason?

Arrange the following steps in sequential order to demonstrate the magnetic effect of the elctric cur-rent using magnetic compass. (A) Wind an insulated conducting wire around the magnetic compass such that the axis of the coil is directed along east west direction and con-nect the free ends of the wire to a cell through a switch. (B) Take a magnetic compass. (C ) When current flows through the conducting wire, it behaves as a magnet and deflects the compass needle. (D) When the switch is closed, the magnetic nee-dle in the compass deflects from its initial posi-tion and when the switch is opend, the needle comes back to its initial position.

In a deflection magnetometer which is adjusted in the usual way. When a magnet is introduced, the deflection observed is theta and the period of oscillation of the needle in the magnetometer is T . When the magnet is removed, the period of oscillation is T_(0) . The relation between T and T_(0) is

When a short bar magnet is kept in tan A position on a deflection magnetometer, the magnetic needle oscillates with a frequency 'f' and the deflection produced is 45^(0) . If the bar magnet is removed find the frequency of osicullation of that needle ?

Name three factors which may be responsible for the disease.