Thursday 26 May 2016

Ohm's Law

In 1827, This dude a German physicist Georg Simon Ohm (1787–1854) found out the relationship between the current I, flowing in a metallic wire and the potential difference across its terminals. He stated that the electric current flowing through a metallic wire is directly proportional to the potential difference V, across its ends provided its temperature remains the same. This is called Ohm’s law.

Ohm's Law state that current ' I ' flowing through a metal conductor is directly proportional to the potential difference ' V ' across the conductor. if temperature is constant.

This graph that current against voltage show when the conductor obey the ohm's law that will be the straight line.The formula for this is :
                                                                           OR


The resistance ' R ' of a conductor define as the ratio of the potential difference for voltage ' V ' across the current ' I ' flowing through it.
 The dotted line show that resistance is stable with constant temperature. So it's mean when the current ' I ' flowing through a conductor ,the potential difference ' V ' also increase. So the formula for this is

Calculation Of Ohm's Law

We have formulas for ohms law now. So it's easy to find out the valve of voltage,current and resistance. So let see some examples. This example is based on the schematic below.
1) If the the current is 6A and the value of resistor is 2Ω. Find the value of voltage ' V '

Steps : Formula V=I x R
                          V= 6 x 2
                                12V

2) If the voltage is 12V and the resistance is  2Ω. Find the value of Current ' I ' 

Steps : Formula I = V/R
                          I = 12/2
                                 6A

3) If the voltage is 12V and the current is 6A. Find the value is resistance  ' R ' 

Steps : Formula R = V/I
                          R = 12/6
                                  2Ω

Easy rite.Don't forget to put symbol for each value. So now you able to understand ohm's law and able to calculate the value of  unit in the circuit. Just you need a circuit and some exercise. 




 

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