Consider the relationship of tension and potential in an electric field.Let's say we have some positively charged body.This body is surrounded by an electric field.Fast forward to this field of positive charge, when transferring the work which will be performed.The value of this work is directly proportional to the size of the charge and, depending on its place in the movement.If we take the ratio of A perfect work to the value of the transferred charge q, then the value of this relationship A / q is not dependent on the amount of charge that is transferred, and is dependent only on the choice of points of movement, the shape of the path is not important.
We substitute the charge in the field, moving it from the infinitely distant point, where the field strength is zero.The value of the relationship of the work will have to perform at the same time against the forces of electric field to the amount of charge that is transferred will be dependent only on the position of the last point move.Consequently, such a value is used for the characterization of a point of the field.
value of which measured by the ratio of work performed during the transfer of a positive charge to a certain point field from infinity to the amount of charge that moves is called the potential of the field.
clear from the definition that at some point the potential of the field is the work that is done by moving a positive charge at a given point of infinity.
potential value denoted by the letter φ:
φ = A / q
potential - scalar quantity.The potentials of each point of the field positively charged body have a positive value, and the potentials of the body with a negative charge have a negative value.
demonstrate that the relationship between the value of the work that is done when moving a positive charge to the amount of charge transferred is equal to the difference between the potential points of movement.
potential difference of two different points of the field, thus, called field intensity between these points.If the voltage of the field designated by the letter U, the connection between the strength and the potential is expressed by the equation:
U = φ₁ - φ₂
This definition is boundless potential of the point will be zero.In this case we say that the point of zero potential may be an arbitrary point of the field, the choice of her immaculate condition.The potential difference between two arbitrary points of the field does not depend on the chosen point of zero potential.
The theoretical work zero point potential acts point at infinity.But in practice - any point of the earth's surface.
Thus, the potential of physics - a value that is measured by the ratio of working when moving a positive charge from the surface to a certain point of the field to the value of the charge.
connection between tension and potential expresses the characteristic of the electric field.Moreover, if the tension is its power characteristics and to determine the amount of force acting on a charge in an arbitrarily chosen point of the field, the potential - its power characteristics.At potentials at various points in electric field can determine the value of the work on the movement of the charge using the formula:
A = qU, or A = q (φ₁ - φ₂),
where q - the magnitude of the charge, U - the voltage between the points of the fieldand φ₁, φ₂ - potential points of movement.
Consider the relationship between the strength and potential in-one electric field.Tension E at every point of the field is the same, and hence the force F, which acts on one charge, too, is the same and equal to E. From this it follows that the force which acts on the charge q in this field will be equal to F = qE.
If the distance between the two points of this field is equal to d, then when you move the charge to perform work:
A = Fd = gEd = g (φ₁-φ₂),
where φ₁-φ₂ is the difference of potential between the points of the field.
here:
E = (φ₁-φ₂) / d,
ieuniform electric field strength is equal to the potential difference that per unit of length, which took on the power line of the field.
At small distances the connection between the strength and the potential is defined similarly and in a nonuniform field, since any field between two closely spaced dots can be mistaken for a uniform.
