What is the difference between electric potential energy and electric potential difference?
Electric potential energy is the potential energy stored when charges are out of equilibrium (like gravitational potential energy). Electric potential is the same, but per charge, U e q . An electric potential difference between two points is called voltage, V = U e 2 q − U e 1 q .
By definition, the electric potential difference is the difference in electric potential (V) between the final and the initial location when work is done upon a charge to change its potential energy.
- Potential Difference. Potential difference , or voltage, is the difference in electric potential energy between two points. It is denoted by ∆V and has units of volts, or joules per Coulomb. Potential is the specific potential energy.
- Measuring Resistance. The symbol "V" is used to represent something called the potential difference. Potential difference is the amount of work done in moving a charge between two points, divided by the size of the charge. That's kind of complicated, though. You can think of potential as electrical height.
- The standard metric unit on electric potential difference is the volt, abbreviated V and named in honor of Alessandro Volta. One Volt is equivalent to one Joule per Coulomb.
An electric potential (also called the electric field potential, potential drop or the electrostatic potential) is the amount of work needed to move a unit positive charge from a reference point to a specific point inside the field without producing any acceleration.
- It is also important to note that potential energy can be positive, zero or negative. For example, if the datum is defined as the top of a table, and the object is on the floor, that object has a negative potential energy since the height below the top of the table.
- Note that if q is negative, its sigh should be used in the equation! Therefore, a system consisting of a negative and a positive point-like charge has a negative potential energy. A negative potential energy means that work must be done against the electric field in moving the charges apart!
- In this case the "altitude" is electric potential or voltage. Equipotential lines are always perpendicular to the electric field. In three dimensions, the lines form equipotential surfaces. Movement along an equipotential surface requires no work because such movement is always perpendicular to the electric field.
If the electric potential difference between two locations is 3 volts, then one coulomb of charge will gain 3 joules of potential energy when moved between those two locations. Because electric potential difference is expressed in units of volts, it is sometimes referred to as the voltage.
- Potential difference (V) – is measured in volts (V). Potential difference is the work done per unit charge. A potential difference of 1 V means that 1 joule of work is done per coulomb of charge.
- The potential difference (voltage) across an ideal conductor is proportional to the current through it. The constant of proportionality is called the "resistance", R. Ohm's Law is given by: V = I R where V is the potential difference between two points which include a resistance R.
- One Volt is equivalent to one Joule per Coulomb. If the electric potential difference between two locations is 1 volt, then one Coulomb of charge will gain 1 joule of potential energy when moved between those two locations.
Updated: 17th October 2019