ahmedhassan72 said:
please what is the charge and is there anything else except +ve -ve and neutral and what is the electric field?
When either a rubber rod or a glass rod is rubbed with a particular material it will become “electrified” in that it will attract small bits of paper or cloth. The process of rubbing the rod is called charging the rod and the physical change on the rod is that the amount of something on the rod either increases or decreases. This “something” is now referred to as charge. In the days of Benjamin Franklin it was thought that charge was a type of invisible fluid present in all matter. Franklin showed that charge comes in both positive and negative quantities. In fact it was Franklin who coined the terms negative charge and positive charge and hence the term charge was coined. The terms negative and positive refer to whether the charges attract or repel each other. Like charges attract while unlike charges repel. In the years following Franklin it was shown that what was either leaving or gaining charge was the change in the number of charged particles we call electrons. (From the Greek word for elektron which means amber).
I don't want to know on what it depends but i want to know what is it matter or what ...
Its an intrinsic
property of certain particles/bodies. It is not matter itself just as
mass is not matter but merely a
property of matter.
...and then comes my question why a force of magnetic field moves a wire from the high magnetic flux to the low magnetic one density can one reverse it ?
A magnetic field exerts a force on a current carrying wire regardless of the magnetic flux density. In fact if you placed a current carrying wire in a uniform magnetic field such that the direction of the current is perpendicular to the direction of the magnetic field then the magnetic field exerts a force on the wire. As to why; It is an experimental fact that a charged particle moving through a magnetic field will have a force exerted on it by the magnetic field when there is a component of the velocity which is perpendicular to the field direction. Since this is taken as a basic law of physics and not something which can be derived from something more basic, i.e. it is a postulate/axiom/law.
Don't tell me that charge is a property ...
Sorry. No can do since that is what it is. I'[m not one for lying and since this
is the truth then this is what I'm posting. Feel free to ignore this post if this is not what you want to read.
..i know i want to know why as an example an electron takes it's -ve charge ?
What is "ve" charge?? What do you mean by "
takes it's -ve charge"? The charge of a particle is usually denoted using the letter "q." The charge on an electron is usually denoted by "e."
many questions also why is the nucleus sphered ...
The nucleus for large number of nucleons is spherical because the shape of the sphere will given the lowest energy state of the nucleus. However when a nucleus is bombarded by other particles, such as neutrons, it will undergo changes in shape and it some cases will break apart into two or more nuclei.
and why electrons revolve in circular orbits not any other shape ...
Electrons move in circular orbits only in special cases. One such case is a charged particle moving through a uniform magnetic field (in this case the electric field is chosen to be zero) and whose initial velocity is in the a plane whose normal vector is parallel to the magnetic field. Since the magnetic field cannot do work on a charged particle (since the force is always perpendicular to the velocity and tus F*dr = 0 an therefore the kinetic energy remains constant. The potential energy is constant since there is no electric field and thus the total energy is constant. The proper mass of the electron doesn't change). Since the force is perpendicular to the velocity it follows that the angular momentum is constant. Since the force on an electron moving in a uniform magnetic field is not a function of position it can be shown that the radial velocity is zero and the angular velocity is constant. This is the description of a particle moving in a circle. If the particle has a velocity which is parallel to the magnetic field then it won't move in a cirlel but in a helical trajectory.
and can we change the charge of electron?
Nothing like this has evern been observed under an enormous variety of situations. That's about all that can be said.
or reverse it's path or stop it ?
No, not in a puer magnetic field (i.e. electric field is zero). If it did then the energy would change and thus the law of conservation of energy would would be broken.
Best wishes
Pete