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Uniformly charged thin spherical shell.

Charged Spherical shell - The sphere is centered in the charged spherical shell's midway. The radius of the Gaussian sphere is larger than the radius of the charged shell when computing the intensity outside the shell. The entire charge is dispersed throughout the shell. The charge density and the volume of the shell determine the charge.

Flux through a closed cylindrical surface of height h, radius r and the same centre as the shell is given as the electric field. The cylinder’s centre is a point on its axis that is equidistant from its top and bottom surfaces. 

The sphere is centred in the charged spherical shell’s midway. The radius of the Gaussian sphere is larger than the radius of the charged shell when computing the intensity outside the shell. The entire charge is dispersed throughout the shell. The charge density and the volume of the shell determine the charge. 

Explain about the field due to uniformly charged thin spherical shell

 

Let R be the radius of a thin spherical shell with uniform surface charge density. There is evident spherical symmetry in the situation. 

 

 

  1. Field outside the shell – Consider the radius vector r of a point P outside the shell. To compute E at P, we use a sphere with radius r and a centre O that passes through P as the Gaussian surface. In relation to the specified charged configuration, all points on this sphere are comparable (spherical symmetry). As a result, the electric field at each point of the Gaussian surface has the same magnitude E and is parallel to the radius vector. As a result, E and S are parallel at all points, and the flux through each element is E S. The flux across the Gaussian surface isE4r2 when all S are added together. According to Gauss’s law.

 

E4r2=04R2

Or, E =R20r2=q40r2 

 

In vector form,

E=q40r2r

 

If q > 0, the electric field is directed outward; if q 0, the electric field is directed inward. This, on the other hand, is the field created by a charge q put in the centre of the O. As a result, the field due to an evenly charged shell is as if the entire charge of the shell is concentrated at its centre for points outside the shell.

  1. Field inside the shell – The point P is inside the shell in Fig. (b). The Gaussian surface is a sphere through P that is centred at O once more.

 

E × 4π r2, as determined previously, is the flow via the Gaussian surface. The Gaussian surface, on the other hand, does not contain any charge in this scenario. Then there’s Gauss’ law. 

E × 4π r2 = 0

 

i.e., E = 0 (r < R), which means that the field generated by a uniformly charged thin shell is zero at all places inside the shell. Gauss’s law, which comes from Coulomb’s law, leads to this significant result. The 1/r2 dependence in Coulomb’s law is confirmed by experimental verification. 

Electrostatic Field

An electrostatic field exists between two objects in close proximity that have distinct electrical charges. When charge carriers, such as electrons, are immobile, electrostatic fields can form as a result of a potential difference or voltage gradient (hence the “static”in “electrostatic”).

 

Electrostatic fields, whose use is frequently referred to as electrohydrodynamics (EHD), are gaining popularity as a method for improving heat and mass transmission. The high voltages (and low currents) associated with such fields are reflected in enhanced activity close to the heat transfer surface, and are often limited to dielectric fluids such as refrigerants and transformer oil. Boiling and condensation have both been improved using this method. (For a historical overview, see Allen and Karayiannis (1995).)

 

The placement of electrodes to produce strong EHD fields close to the surface of a heat exchanger tube is critical to maximising the influence of the electric field. Engineers interested in intensifying a process may be able to map field strength to provide the best results by selecting the right electrodes and placing them in the right places.  

Conclusion

In the above articles we have seen a derivation of the field due to uniformly charged thin spherical shells.  

In that derivation we have seen two conditions 

  1. Field Outside the shell

  2. Field Inside the shell

And we also have seen the Electrostatic field,

What can we conclude from the Electrostatic field?

Electrostatic methods are appealing for separating particle mixtures because they are dry, consume little energy, and produce minimum environmental emissions. Traditional electrostatic techniques for industrial minerals, on the other hand, are unable to separate fine particles such as fly ash, where the majority of particles are smaller than 100 microns. Electrostatic separation procedures are severely limited by these small particles.

 
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Frequently asked questions

Get answers to the most common queries related to the NEET UG Examination Preparation.

What is the greatest electric field owing to a charged spherical shell?

Ans: The electric intensity is highest at any point on the shell’s surface.

 

What causes the charge within a spherical shell to be zero?

Ans: Because charge does not reside within it, it goes outside its surface, creating an electric field inside zero. ...Read full