NEET-XII-Physics
36: Permanent Magnets
- #4Figure (36-E1) shows some of the equipotential surfaces of the magnetic scalar potential. Find the magnetic field B at a point in the region.
Figure
Ans : Given:
Perpendicular distance, dx = 10 sin30â‚’ cm = 0.05 m,
Change in the potential, dV = 0.1 × 10-4 T-m
We know that the relation between the potential and the field is given by
`` B=-\frac{dV}{dx}``
`` \Rightarrow B=-\frac{0.1\times {10}^{-4}\,\mathrm{\,T\,}-m}{5\times {10}^{-2}m}``
`` \Rightarrow B=-2\times {10}^{-4}\,\mathrm{\,T\,}``
B is perpendicular to the equipotential surface. Here, it is at angle of 120° with the positive x-axis.
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