|
What is Electricity? |
 |
In short, electricity is the movement of electrons. When you have a "potential difference" a negative charge (cathode) and a positive charge (anode) connected by a conductor, electrons will move from negative to positive, creating electricity. The amount of potential difference is called voltage, it creates the force behind the movement of electrons, the more potential difference, the more voltage. I like to call voltage the 'amount of attraction from negative to positive', it is easier to visualize that way. If we increase the force or voltage, we will also increase the rate at which electrons are flowing, the current, in direct proportion. In other words, if we increase the voltage, the current will increase the same amount. What happens when we put something (a load) in the path of electrical current? That creates resistance. The greater the resistance, the slower the current. Therefore, current and resistance are inversely proportionate, if one goes up, the other goes down and vice versa. This explains the relationship of voltage, current and resistance and why the Ohm's Law chart is the way it is...
 |
|
What is Ohm's Law?Ohm's Law identifies the proportional relationship between voltage, current and resistance in electricity: It takes one volt to push one amp through one ohm. Because of this relationship, mathematical formulas can be used to calculate a missing quantity. Below are definitions of the basic quantities of electricity (voltage, current and resisitance) and a table of Ohm's Law formulas. Voltage (V): Measured in Volts, also known as Electromotive Force (EMF). Voltage is the force (provided by an external source such as batteries) that creates the negative to positive attraction that drives electrons through a circuit. Current (I): Measured in Amps (amperes). Current is the rate at which electrons are flowing in the circuit. Resistance (R): Measured in Ohms. Resistance is the holding back of electrons, making it difficult for current to flow. Resistance is created by loads such as lights, motors (and of course resistors). Ohm's Law FormulasVoltage (E) | Current (I) | Resistance (R) | | Measured in Volts | Measured in Amperes (amps) | Measured in ohms | | E=IxR | I=E/R | R=E/I | Needed to force “x” amount of current through a circuit and is equal to the current multiplied by the resistance | The current flowing through a circuit equals to the voltage divided by the resistance | The resistance within a circuit equals the voltage divided by the current. |
|
|
|
|
