A magnetic needle has a frequency of `20` oscillations per minute in the earth's horizontal field. When the field of a manget supports the earths horizontal field, the frequency increases to `30` oscillations per minute. The ration of the field of the magnet to that of the earth is

Lines of force due to earth's horizontal magnetic field are

A small magnetic needle performs 10 oscillations/minute in the earth's horizontal magnetic field . When a bar magnet is placed near the small magnet in same position , frequency of oscillations becomes 10sqrt2 oscillations/minute . If the bar magnet be turned around end to end , the rate of oscillation of small magnet will become

A small magnetic needle performs 10 oscillations/minute in the earth's horizontal magnetic field . When a bar magnet is placed near the small magnet in same position , frequency of oscillations becomes 10sqrt2 oscillations/minute . If the bar magnet be turned around end to end , the rate of oscillation of small magnet will become

Lines of force, due to earth's horizontal magnetic field are.

A compose needle makes 10 oscillations per minute in the earths horizontal field. A bar magnet deflects the needle by 60^(@) from the magnetic meridian. The frequency of oscillaiton in the deflected position in oscillations per minute is (field due to magnet is perpendicular to B_(H) )

The magnetic needle of a vibration magnetometer makes 12 oscillations per minute in the horizontal component of earth's magnetic field. When an external short bar magnet is placed at some line, it makes 15 oscillations per minute, If the poles of the bar magnet are interchanged, the number of oscillations it makes per minute is

The magnetic needle of an oscillation magnetometer makes 10 oscillations per minut under the action of earth's magnetic field along. When a bar magnet is placed at some distance along the axis of the needle it makes 14 oscillations per minute. If the bar magnet is turned so that its poles interchange their position, then the new frequency of oscillation of the needle is: