Home » Posts tagged 'electric field'

Tag Archives: electric field

Electromagnetic waves of a charged particle

If there is a charged particle moving with constant velocity then at any point in space magnitude of electric and magnetic field changes with time. changing magnetic field will produce electric field and changing electric field will produce magnetic field subsequently. if it is so then it should emit EM waves.How to explain it from the frame in which charge is moving with constant velocity?how to explain this from the frame of reference in which the charge is moving at constant velocity?

Asked Rajesh Kumar Nayak

Nature of Electromagnetic Waves

When we represent the frequency, amplitude, and wavelength of any electromagnetic radiation on a graph we see a wave like in water. Is this just a geometric representation or do the “packet” aspects of these waves actually move physically like the mathematical representation.

Asked Jack Cassidy

Hope that the following videos explain the concept better

English: Electromagnetic waves can be imagined...
English: Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. This diagram shows a plane linearly polarized wave propagating from left to right. The electric field is in a vertical plane and the magnetic field in a horizontal plane. http://weelookang.blogspot.com/2011/10/ejs-open-source-propagation-of.html (Photo credit: Wikipedia)



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.

 

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...

 

 

A question from electric field

An insulating sphere of mass m and positive charge q is attached to a spring with length h and spring constant k and is at equilibrium. An infinitely long wire with positive linear charge density λ is placed a distance l away from the charged mass at equilibrium (note that the position of the top of the spring is fixed). The previous length of the spring was h. What is the new length of the spring in terms of h, q, k, λ, l as needed.

%d bloggers like this: