## sábado, 25 de febrero de 2012

### Ohm's law

In this entry I'm going to explain the Ohm's law for the analysis of an electronic circuit.
Ohm's law tells us that the voltage V across a resistor is proportional to the current I flowing through the resistor (R). The way it is the equation with Ohm's law is: V=I*R
Where:
-V is measured in volts and is represented by V, for example, 5volts=5V
-I is the current of the conductor, and is measured in Amperes, represented by A, for example, 10amperes=10A
-R is the resistance of the conductor, measured in Ohm's and denoted by the greek alphabet Omega, for example, 10Ohm's=10Ω

Let's see Ohm's law applied to a simple electrical circuit:
When analyzing an electrical circuit, it must be consider several factors. The polarity of the source, the polarity of the resistor and the current direction. Usually, when an analysis of a circuit is done, it is considered that the current is in clockwise direction, that is:
There are several types of sources for this circuit we will choose the second example of the entry number two. Where the positive power is the largest horizontal bar while the negative will be the smaller horizontal bar. The next thing to do is assign a polarity to the resistance. When a current I passes through a resistor R, it is said that the electric current enters the positive(+) of the resistance and exits through the negative(-). We said that the analysis of a circuit is in the sense of clockwise, so in the circuit, the polarities will be represented as:
Applying the Ohm's law, V=IR, we clear the value of I and we have: I=V/R
We have 12V and 12Ohm, and substituting in the equation: I=12V/12Ohm=1A
If we want to know the voltage of the resistance, since we have the total current value of the circuit, is one ampere(1A), we simply multiply the value of the current flowing through the resistor with the value of it: V=I*R=(1A)(12Ohm)=12V

Conclusion: The voltage provided by a voltage source will be divided equally between the circuit elements.