Ask the Experts: What’s the difference between Volts, Amps and Kilowatt-hours?
Just like water needs pressure to force it through a hose, electrical current needs some force to make it flow. A volt is the measure of electric pressure. Voltage is. You cannot convert watts to amps, since watts are power and amps are amps multiplied by volts, there is a simple relationship between them. Electronics Tutorial about the Relationship between Voltage Current and Resistance in an Electrical Circuit and their relationship using Ohms Law. The Potential difference between two points is measured in Volts with the circuit symbol V.
Electric field calculations of this sort are more of a theoretical physics or special applications problem, so these calculations are omitted here in favor of more applicable material. See Electric Field for such information on electric field formulas. There is an electrical force on a charge only if there is a charge subject to the force at a location in an electric field.
However, even if there is no such charge subject to the force, there could still be an electric field at a point. This means that an electric field is a property of a location or point in space and its electrical environment, which would determine what a charge q would "feel" if it were there.
Energy[ edit ] Now, a micro-physics review: Work is causing displacement or movement of an object or matter against a force. Energy is the ability to perform work like this.
Current, Resistance, Voltage, and Power
Energy can be kinetic energy or potential energy. Kinetic energy is the energy a mass has because it is moving. Potential energy in an object, in matter, in a charge or other situation has the ability to perform work or to be converted into kinetic energy or a different kind of potential energy. A reason why a particle or a charge may have potential energy could be because it is located at a point in a force field, such as a gravitational field, electric field, or magnetic field.
In the presence of such a field, gravity or electric or magnetic forces could cause the particle or charge to move faster or move against resistive forces, representing a conversion of potential energy to kinetic energy or work. The amount of potential energy it has would depend on its location. Moving from one location to another could cause a change in its potential energy.
For example, an object near the surface of the earth placed high would have a certain amount of gravitational potential energy based on its mass, location height or altitude in and strength of the Earth's gravitational field.
If the object were to drop from this location height to a new lower location, at least some of its gravitational potential energy would be converted to kinetic energy, resulting in the object moving down. The difference in gravitational potential energy could be calculated from one location to another, but determining the absolute potential energy of the object is arbitrary, so ground level is chosen arbitrarily as the height where its gravitational potential energy equals zero.
The potential energy at all other heights is determined from the mass of the object, location relative to the ground level, and strength of the gravitational field. All energy values are numerical or scalar quantities, not vectors. Electric Potential Energy[ edit ] Somewhat similarly, a charged particle at a certain point or location in an electrical environment i.
If the charge were to move from this location to a new location or point, it could cause a change in its electric potential energy. This difference in electric potential energy in the charge particle would be proportional to its charge and it could be an increase or a decrease.
From measurements and calculations, one may be able to determine this difference in electric potential energy, but coming up with an absolute figure for its potential is difficult and typically not necessary.
Therefore, in a manner somewhat similar to gravitational potential energy, an arbitrary location or point nearby, often somewhere in the electric circuit in question, is chosen to be the point where the electric potential energy would be zero, if the charge were there. Often the wiring, circuit, or appliance will be connected to the ground, so this ground point is often chosen to be the zero point.
The electric potential energy at all other points is determined relative to the ground level.
The SI unit of electric potential energy is the joule. Electric Potential[ edit ] Because the electric potential energy of a charged particle or object is proportional to its charge and otherwise simply dependent on its location point where it's ata useful value to use is electric potential.
How to Convert Watts to Amps Simplified -- Converting Amps to Watts the easy way
Electric potential symbolized by V at a point is defined as the electric potential energy PE per unit positive charge q that a charge would have at that given point location. At a point a, the electric potential at a is given by: On the other hand, electric potential energy is more analogous to electric force in that for it to be present, there should be a subject charged particle or object which has that energy.
Electric potential is often simply called potential by physicists. Because electric potential energy is based on an arbitrary point where its value is set at as zero, the value of electric potential at a given point is also based on this same arbitrary zero point reference point where the potential is set at zero.
The potential at a given point a is then the difference between potentials from point a to the zero point, often called a ground node or just ground.
Calculations of electric potential energy or electric potential based on Coulomb's Law are sometimes theoretically possible, such as might be for electric field calculations, but again these are of mostly theoretical interest and not often done in practical applications. Materials that follow Ohm's law have a constant resistivity no matter what the values of the electric field E and current density J are. The formulas related to circuits are true for "Ohmic" materials, and "non-Ohmic" materials are not discussed in this course.
The resistivity of an Ohmic conductor depends on the temperature of the material. One Ohm is equal to one Volt per Ampere, Resistance depends on temperature in the same way as resistivity, This formula requires R0, the resistance at a reference temperature T0. A resistor is a device that is used in electric circuits, and has a certain fixed resistance. Resistors are made by choosing a piece of material with a certain resistivity, length, and area, and wrapping it in an insulator with wires leading out of each end.
In circuit diagrams, it is represented with the symbol, Voltage Voltage is a difference in electric potential between two points. A voltage source is a device used in electric circuits that has a fixed potential difference between its ends. A voltage source can be a battery, or another source of direct current with a fixed potential difference. In circuit diagrams, it is represented with the symbol, If the ends of a voltage source are connected through a circuit with any number of resistors or other components, a complete circuit is formed, and current can flow from one terminal to the other.
If current is flowing, it will be the same on both terminals of the voltage source.