Some relationship between current and voltage does exist in an electrical circuit network. Kirchhoff’s Law helps us in solving these relations and also help us understand those. This set of rules helps us in solving many complex circuits, for this reason, explore the article to know more about the Law!

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## Atmospheric Electricity

The global atmospheric electrical circuit is the relation between the Earth’s surface, ionosphere, and the atmosphere. Atmospheric electricity is the regular result of the peak results in earth’s electromagnetic network. The induction of EArth’s surface and other electromagnetic devices is because of the free electricity present in the air and the clouds.

The thunderstorm acts like the batteries of the atmosphere providing the atmosphere with the charge it needs. The atmospheric electricity charges the ionosphere up to 400,000 volts with respect to earth’s surface. Lighting is caused due to electric discharge is proved by some physicists experimenters.

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## Kirchhoff’s Law

In 1845, Gustav Kirchoff, a German physicist, developed a set of rules and theorems. To deal with the conservation of energy and potential difference within the circuit. Kirchhoff’s Law helps us in solving complex relation between current and potential difference commonly known as voltage. The 2 rules developed are Kirchhoff’s Current Law and Kirchhoff’s Voltage Law. Electrical Engineering widely uses this Law.

**1. Kirchhoff’s Current Law**

Kirchhoff’s Current rule, in other words, is Kirchhoff’s first Law, Kirchhoff’s point rule or Kirchhoff’s junction rule. The principle of conservation of electric charges states that: At any node ( junction ) in an electrical circuit, the sum of all currents flowing into that node is equal to the sum of currents flowing out of that node or equivalently.

If I_{1}, I_{2}, and I_{3} are current entering junction and I4 and I5 are current leaving junction. Then the sun of all Current entering and leaving junction is always zero, in the case of Kirchhoff’s Current Law.

**I _{1}+I_{2}+I_{3}-I_{4}-I_{5}=0**

Adding all the Current entering junctions and subtracting all the Current leaving junctions the Current Law is derived, as the result of this equation, the result will always be Zero. Therefore, we conclude Kirchhoff’s current Law or Kirchhoff’s First Law.

### 2. **Kirchhoff’s Voltage Law**

Kirchhoff’s Voltage Law, in other words, is Kirchhoff’s Second Law, Kirchhoff’s loop (or mesh). The principle of conservation of energy states that the directed sum of the electrical potential difference (Voltage) around any closed network is zero. In other words, the sum of all EMFs is equivalent to the sum the potential drops in the closed electrical network.

The algebraic sum of the emf available in the closed loop electric network is equivalent to the product of all the resistance of the conductors and the current in the closed loop. In conclusion, the circuit should have the sum of Voltage drop to zero.

## Solved Examples for You

Question 1: The layer of the earth’s atmosphere which contains a high concentration of ions and free electrons and is able to reflect radio wave is known as

- Ionosphere
- Stratosphere
- Mesosphere
- Exosphere

Solution: Option A. Ionosphere, The layer of the earth’s atmosphere which contains a high concentration of ions and free electrons and is able to reflect radio wave is known as the ionosphere.

Question 2: In the following circuit, the battery E_{1} has an emf of 12V and zero internal resistance while the battery E has emf of 2V If the galvanometer G reads zero, then the value of the resistance X in ohm is

- 10
- 100
- 500
- 200

Solution: Option B. I_{1}=12/(500+x), I_{2}=2/x. As the galvanometer has zero deflection we have 12/(500+x)=2/x or x=100 ohms.

3. The normal movement of electric charges among the Earth’s surface, the various layers of the atmosphere, and especially the ionosphere, taken together, are known as :

- a current conducting circuit
- the global atmospheric electrical circuit
- charge cloud
- none of the above

Solution: Option C. The global atmospheric electrical circuit.