How is electrical work measured?
So if 1 watt = 1 joule per second, it therefore follows that: 1 Joule of energy = 1 watt over one unit of time, that is: Work equals Power multiplied by Time, (V*I*t joules). So electrical energy (the work done) is obtained by multiplying power by the time in seconds that the charge (in the form of a current) flows.
What is the unit of measure for electrical force?
Newton
What is needed for electricity to work?
To produce an electric current, three things are needed: a supply of electric charges (electrons) which are free to flow, some form of push to move the charges through the circuit and a pathway to carry the charges. The flow of electricity can be likened to a flow of water through a pipe.
What is the unit for resistance volt ampere Ohm Coulomb?
The unit of current is the ampere (A), and means one coulomb per second. The unit of potential difference is the volt (V), and means one joule per coulomb. The unit of resistance is the ohm (Ω), and is equal to voltage over current.
What is the relationship between resistance and current?
The relationship between current, voltage and resistance is expressed by Ohm’s Law. This states that the current flowing in a circuit is directly proportional to the applied voltage and inversely proportional to the resistance of the circuit, provided the temperature remains constant.
What is the difference between voltage and current?
Voltage is the difference in charge between two points. Current is the rate at which charge is flowing.
What are the four factors that affect resistance?
Factors That Affect Resistance How much resistance a material has depends on several factors: the type of material, its width, its length, and its temperature.
What is resistance and what factors affect it?
Resistance is the property of the material that restricts the flow of electrons. There are four factors affecting resistance which are Temperature, Length of wire, Area of the cross-section of the wire, and nature of the material.
What are the two factors that influence resistance?
There are several factors that affect the resistance of a conductor;
- material, eg copper, has lower resistance than steel.
- length – longer wires have greater resistance.
- thickness – smaller diameter wires have greater resistance.
- temperature – heating a wire increases its resistance.
How does resistance affect voltage?
Ohm’s law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Similarly, increasing the resistance of the circuit will lower the current flow if the voltage is not changed.