Physics-
General
Easy
Question
An ellipsoidal cavity is carved within a perfect conductor. A positive charge 
is placed at the centre of the cavity. The points 
and 
are on the cavity surface as shown in the figure. Then
- Electric field near in the cavity = Electric field near in the cavity
- Charge density at
Charge density at
- Potential at Potential at
- Total electric field flux through the surface of the cavity is
in the cavity = Electric field near in the cavity
Charge density at
Potential at
The correct answer is: Potential at Potential at
Under electrostatic condition, all points lying on the conductor are in same potential. Therefore, potential at A = potential at B.
From Gauss's theorem, total flux through the surface of the cavity will be q/e0.
Note : q Instead of an elliptical cavity, if it would had been a spherical cavity then options (a) and (b) were also correct
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