Ohm’s Law: Definition, Statement, Application And Limitations

Ohm’s Law; Definition, Statement, Application And Limitations: The current that flows through most conductors is directly proportional to the voltage applied. 

What Is Ohm’s Law? 

Ohm’s Law states that the amount of current flowing through the conductor is directly proportional to the voltage applied across it, provided all other conditions like the temperature remain constant. 

Formula For Ohm’s Law

V= IR 

where V is the voltage, I is the current and R is the resistance. 

The same formula can be rewritten in many different ways to calculate the current and resistance as follows:-

I= V/R

R=V/I

Ohm’s Law Statement

It states that the voltage across a conductor is directly proportional to the current flowing through it. 

Relationship Between Voltage, Current and Resistance

Voltage, current and resistance are the fundamental building blocks of understanding electrical circuits. Their relationship can be explained with the help of Ohm’s Law which describes how the quantities interact. 

As, V = IR

• Voltage is directly proportional to the current flowing through a circuit. 
• Voltage is inversely proportional to the resistance in the circuit. 

Experimental Verification Of Ohm’s Law

Ohm’s Law can be verified using the following experiment. 

Apparatus Needed

Resistor, Ammeter, Voltmeter, Battery, Plug Key, Rheostat

Circuit Diagram

The Procedure

• At the start, key K is closed and the rheostat is adjusted to get the minimum reading in the ammeter A and voltmeter V.
• The current increases gradually by moving the sliding terminal of the rheostat. The current flowing and correspondent value of potential difference can be recorded. 
• This, one can get different values of current and voltage. 
• The ratio V/I is calculated. 
• When you calculate the ratio, you will come to see that it is constant. 
• Plot a graph and it will be a straight line. This shows that the current is proportional to the potential difference.

Applications Of Ohm’s Law

The main applications of Ohm’s law are as follows: 

• To determine the voltage, current and resistance of an electric circuit. 
• Ohm's law can be used to calculate the power dissipated in a circuit. 
• In circuits with multiple components, it is important to ensure that the desired voltage reaches each component. Omh’s law helps to maintain the desired voltage drop. 

Limitations Of Ohm’s Law

• Ohm's law applies only to ohmic materials. These are the materials where the current flowing through them is directly proportional to the applied voltage. 
• Ohm’s law does not apply to unilateral electrical appliances like diodes and transistors as they allow the current to flow through in one direction only. 

Students can take a look at these concepts and get a basic understanding of Ohm’s Law. For more such updates, keep following Jagran Josh. 

Other Related Links

• Value Of R In Gas Constant: Definition, Introduction, Value And Applications!

• Newton’s Second Law Of Motion: Definition, Application, Derivation And Examples!