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# Few question regardinf electricy and magnetism

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what is the differrence between positive ions and proton similarly negative ion and electron?

how come oppositely charged ions produce electric field?

what is the difference between magnetic and electric field?

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what is the differrence between positive ions and proton similarly negative ion and electron?

A postive ion is any atom with an overall positive charge. Eg Oxygen with 8 protons and 7 electrons = O+. A proton is just the fundamental charge particle responsible for + charge (ignorning particle theory).

A negitive ion is any atom with an overall negative charge (eg O- with 8 protons and 9 electrons). An electron is the fundamental charge particle responsible for - charge.

how come oppositely charged ions produce electric field?

All charged objects produce an electric field almost by definition. Charge simply causes a force between other charged objects. An electric field is simply the vector force applied to a unit +ve charge in the given environment. Thus when you have any charged particles there will be an electric field moving away from +ve charge and towards -ve Charge.

what is the difference between magnetic and electric field?

One can say that an electric field is caused by stationary charged objects and a magnetic field is caused by a flow of charge (ie a current).

However I recommend stunning your teacher by saying that both the electric field and the magnetic field are, under special relativity, both the same effects but an electric field results when you are in the frame of the charge and magnetic field effects occur when the charge is moving in the frame of the observer.

If you teacher says that your wrong for saying that electric field = magnetic field tell her "no, your wrong". Possibly tell your teacher to read a text book called 'spacetime physics' or any other detailed special relativity textbook.

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electric field is defined as force per charge $\vec{F}/q$ if you place another charge near a charge, the "other" chrage will certainly experiences a force, the electric can be calculated as force divided by the charge of "the other charge" (assume the other charge has no effect on the first charge)

before the unification of the two, magnetic and electric are considered as two separate things. magnetic field is definied as $\frac{F}{qv}$. the direction of the field can be experimentally determined. the direction is the same as the direction of the compass if it is places at that location. So, magnetic field only excerts a force on a MOVING charge, not just any charge while a presence of a electric field will excert forces on any charge (be it positive or negative).

to calculate force for electric field, one simply multiply the field E vector by charge, however, in a magnetic field, it is quite different.

$\vec{F_b}=q\vec{v}\times{\vec{B}}$ here the cross product is used, this is experimentally determined back in the old days.

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