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Electric potential due to a dipole

If a point lies at a distance x from the midpoint of the dipole the electric potential is?

 

Asked Sai Mohan

 

Answer:

 

If the distance x is along the equatorial plane (a plane passing through the midpoint and perpendicular to the axis), the potential will be zero.

 

Please clarify what did you mean.

 

English: Potential field due to an electric dipole
English: Potential field due to an electric dipole (Photo credit: Wikipedia)

 

 

Explain a method to create Uniform Electric Field.

Relativistic electromagnetism (fig. 1): Two op...
Two oppositely charged plates produce a uniform electric field even when moving.(Photo credit: Wikipedia)

 

The simplest method of creating a uniform electric field in a region is to keep two  equally charged thin plain metal sheets of opposite charge parallel to each other. As you can see from the derivation for electric field due to a plain sheet of charge, the electric field due to a plain sheet of charge is independent of distance (provided the distance is not large compared to the dimensions of the plain sheet of charge).

 

So, if you keep two plain metal sheets of same charge densities but opposite kind of charge, we get a fairly good uniform electric field in between the plates.

 

At regions close to a uniformly charged thin sheet also we get a uniform electric field, but as distance increases it may tend to become non uniform.

 

Electricity field intensity within a conductor is always zero.Why?

Electricity field intensity within a conductor is always zero.Why?

Asked Shaji

Answer:

The main difference between a conductor and an insulator is that the conductors contain plenty of free electrons which are free to move throughout the conductor; whereas the insulators do not have free electrons at room temperature.

When a conductor is held in an electric field, the free electrons inside them instantly drift opposite to the direction of electric field until the electric field due to the drift balances the external electric field and the net electric field inside the conductor becomes zero.

 

Sensitivity of Wheatstone’s Bridge

When does the sensitivity of a wheatstone bridge reduce?

 

Asked Shreya

 

Answer:

 

Sensitivity refers to a large deflection for a small imbalance of the bridge.

 

Now try to identify the factors contributing to sensitivity!

 

Wheatstone bridge using Thomson galvanometer

 

Electricity from ocean currents

How can we produce electricity using currents in ocean?

Asked Saurabh Pathak

Answer:

Electricty can be generated from ocean through various means, mainly

  • Ocean Thermal Energy Devices
  • Tidal Energy
  • Energy of waves and
  • Ocean Currents

The energy extraction from ocean currents is somewhat analogous to energy from winds. (ref http://www.boem.gov/Renewable-Energy-Program/Renewable-Energy-Guide/Ocean-Current-Energy.aspx)

Ocean current technology is still in its early stage of development.

For ocean current energy to be utilized successfully at a commercial scale, a number of engineering and technical challenges need to be addressed, including:

  •  avoidance of cavitations (bubble formation);
  •  prevention of marine growth buildup;
  •  reliability (since maintenance costs are potentially high); and
  •  corrosion resistance.
GDE Error: Error retrieving file - if necessary turn off error checking (303:See Other)

 

What is charge basically?

It may be rather silly but still I’m really curious to know about this.  What is charge basically?  I’m tired of reading and hearing charge is an inherent property of matter,  it is that which causes electric field etc.

 

Asked Sudha

 

Answer:

 

First of all, I would like to tell that I am interested mainly in such questions which are branded silly. But many of those silly branded questions are not so silly.

 

Charge is defined in intermediate Physics as below

 

“Electric charge is the physical property of matter that causes it to experience a force when close to other electrically charged matter. “

 

The concept of electric field was introduced by Faraday to explain how two charges exert force on each other without physical contact. A charged particle (and also a time varying magnetic field) produces an electric field.

 

English: Field of a positive point charge. Thu...

 

 

Average Speed and Average Velocity

The average velocity of a particle is zero but not its average speed. is it possible?

Asked Prashant

Answer:

Yes, it is possible. As you may probably know, Average speed is the ratio of distance traveled by a body to the time taken whereas average speed is the ratio of displacement to the time taken. The displacement made by a body can be zero when the body returns to its original path. abut, the distance which the total length of the path followed by the body cannot be zero.

Therefore the average velocity of a particle is zero but not its average speed. is it possible?

 

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