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प्रश्न
If the total charge enclosed by a surface is zero, does it imply that the elecric field everywhere on the surface is zero? Conversely, if the electric field everywhere on a surface is zero, does it imply that net charge inside is zero.
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उत्तर
According to Gauss’ law, the flux associated with any closed surface is given by `int_s` E.dS = `q_(enclosed)/ε_0`. The term `q_(enclosed)` on the right side of the equation includes the sum of all charges enclosed by the surface called (Gaussian surface).
In the left side equation, the electric field is due to all the charges present both inside as well as outside the Gaussian surface.
Thus, despite being total charge enclosed by a surface zero, it doesn’t imply that the electric field everywhere on the surface is zero, the field may be normal to the surface.
Also, conversely if the electric field everywhere on a surface is zero.
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संबंधित प्रश्न
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- `oint_s` E.dS = 0 if the charge is outside the surface.
- `oint_s` E.dS could not be defined.
- `oint_s` E.dS = `q/ε_0` if charges of magnitude q were inside the surface.
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- the electric field is necessarily zero.
- the electric field is due to the dipole moment of the charge distribution only.
- the dominant electric field is `∞ 1/r^3`, for large r, where r is the distance from a origin in this region.
- the work done to move a charged particle along a closed path, away from the region, will be zero.
In 1959 Lyttleton and Bondi suggested that the expansion of the Universe could be explained if matter carried a net charge. Suppose that the Universe is made up of hydrogen atoms with a number density N, which is maintained a constant. Let the charge on the proton be: ep = – (1 + y)e where e is the electronic charge.
- Find the critical value of y such that expansion may start.
- Show that the velocity of expansion is proportional to the distance from the centre.
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A charge Q is placed at the centre of a cube. The electric flux through one of its faces is ______.
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For a Gaussian surface to be convenient for calculations, the electric field should be:
The integral form of Gauss's Law is given by:
In the context of Gauss's Law, what does the area element vector dS represent?
For a uniformly charged thin spherical shell, what is the electric field at any point inside the shell (r < R)?
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