- Home
- Standard 12
- Physics
Before using the tangent galvanometer, its coil is set in
Magnetic meridian (or vertically north south)
Perpendicular to magnetic meridian
At angle of ${45^o}$ to magnetic meridian
It does not require any setting
Solution
(a) The tangent magnetometer, works on the tangent law, which in mathematical form states,
$F=H \tan \theta$
where,
$F$, and $H$ are two uniform magnetic fields. Of the two uniform magnetic fields, one is the horizontal component of the earth's magnetic field, the other field is produced by a bar magnet The horizontal component of the earth's magnetic field is along the magnetic meridian i.e. the north south direction. So we first mark the magnetic meridian at the place where we are to do the experiment. We then place the magnetometer box such that the magnetic needle is also $g$ $N-S$ direction. The magnetometer is used in two positions $\tan A$ and $\tan B$
In the tan $A$ position the magnetometer arm is in the east west direction. And the needles points in the $N-S$ direction. The bar magnet is placed on the magnetometer arms with its axis along the $E-W$ direction.
In the tan $B$ position of the magnetometer, the arms are along $N-S$ direction. The bar magnet is placed on the arms of the instrument with its axis along $E-W$ direction.
