Zero Electric Potential

Zero electric potential is a reference point used in electrical engineering and physics to measure the electric potential at other points in a system. In practice, Earth is often chosen as the place of zero electric potential. This choice is based on several factors, including its almost constant potential.

Constant Potential of Earth

The Earth's electric potential remains relatively constant due to the presence of a large conductive surface, such as the Earth's surface itself, which acts as a "ground". This means that the potential difference between any point on the Earth's surface and another point on the Earth's surface is essentially zero. By convention, this is chosen as the reference point for measuring electric potential.

Non-Conducting Earth

It is important to note that the choice of Earth as the reference point for zero electric potential does not depend on whether the Earth is conducting or non-conducting. In fact, the Earth's surface is a good conductor of electricity, as it is made up of materials such as soil and water that contain free charges. However, the choice of Earth as the reference point is not based on the conductivity of the Earth.

Easily Available Reference

Another reason why Earth is chosen as the reference point for zero electric potential is its easy availability. Earth is present everywhere, and it is easily accessible for measurements. This makes it convenient to use Earth as the reference point in electrical engineering and physics experiments.

Loss and Gain of Electric Charge

The fact that Earth keeps losing and gaining electric charge every day does not directly influence the choice of Earth as the reference point for zero electric potential. The loss and gain of electric charge by Earth are natural processes that occur due to various factors such as lightning, atmospheric conditions, and the interaction of Earth with other charged objects. These processes do not affect the overall constant potential of Earth, which is the primary reason for choosing it as the reference point.

In conclusion, Earth is chosen as the place of zero electric potential because it has an almost constant potential, it is easily available as a reference, and its conductivity does not play a significant role in this choice.