Table of Contents

**Meaning of ohm’s law**

The current through a conductor element is proportional to the potential difference applied between its ends, the temperature which is provided remains constant is known as **ohm’s law**.

**Formula: Voltage=CurrentResistance**

V=IR

V=voltage, I=current, R=resistance

**Limitations of ohm’s law**

- Ohm’s law is not applicable if the temperature changes.
- For gaseous materials this ohm’s law is not applicable.
- For semi metallic substances ohm’s law is not applicable.

**Uses of ohm’s law**

- One of the very common devices where the current through the fan gets regulated by controlling the resistance of the regular circuit.
- In voltage divider circuits ohm’s law is used to divide source voltage across the output of the resistance.
- The components such as voltage supplies, current levels and voltage drops etc ohm’s law is used to validate the static values of circuit components.

**Applications of ohm’s law**

- The main application of ohm’s law is to determine the voltage, resistance or current of an electric current.
- Another application of ohm’s law is it is mainly used in dc ammeter and other dc measuring instruments.
- Last but not the least application of ohm’s law is across the electronic component ohm’s law is used to maintain the desired voltage drop. Actually it’s one of the best experiments to learn about ohm’s law. So now we are going to discuss the experiment of ohm’s law.

**Ohm’s law experiment**

**Aim:** To show that the ratio of V/I is constant for a conductor.

**Materials required**

- 5 dry cells of 1.5V each
- Connecting wires of ammeter
- Voltmeter
- Thin iron
- Key

**Ohm’s law procedure**

- Connect a circuit.
- Solder the connecting wires to the ends of the iron spoke.
- Note down the readings of current by closing the key from ammeter and potential difference from voltmeter.
- Now connect two cells instead of one cell in the circuit.
- Note down the readings of the ammeter and voltmeter and record the observations.

**Observations**

**Conclusion of experiment : **

The ratio of V/I is constant VI and even the potential difference between the ends of the iron spoke is directly proportional to the current passing through it. During the flow the temperature of the iron spoke is constant.

**Conclusion:**

This is the **ohm’s law** experiment which is very easy and important. Even this topic will be repeated in class 12. This is the **class 10 ohm’s law experiment**. It’s very useful and it helps us in many **competitive exams**. Actually it’s a very easy topic to understand and learn.