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Question: Name two factors on which the internal resistance of a cell depends and state how it depends on the ...

Name two factors on which the internal resistance of a cell depends and state how it depends on the factors stated by you.

Explanation

Solution

The internal resistance of the cell is the offered opposition to the flow of current by the cell or the battery. The internal resistance of the battery or the cell can be calculated by using ohm's law. Initially, the value of internal resistance is very small. In ideal cases for easy calculation, it is also considered to be zero.

Complete answer:
Internal resistance is the offered opposition to the flow of current by the cell or the battery. It has a very small value ideally it is considered as zero for easy calculations of complex circuits.
The internal resistance of a cell is dependent on the area of the two plates (electrolytes) of the cell and the distance by which they are apart from each other.
The larger the separation between the plates (electrolytes) the more the current has to travel between the electrolytes which will lead to the greater value of the internal resistance of the cell. The greater the value of internal resistance less will be the value of conductivity.
The internal resistance is inversely proportional to the area of the electrolytes. Greater will be the area less will be the internal resistance of the cell.
So we can say that internal resistance (rr) is directly proportional to the distance between the plates (dd) and inversely to the area of the plates (AA)
rdAr\propto \dfrac{d}{A}
Internal resistance also depends on the nature of the electrolytes used in the formation of cell or battery.

Note:
The internal resistance is neglected when complex calculations are to be performed. But if it has to be considered the internal resistance of a call can be calculated experimentally by using a potentiometer. A potentiometer is an instrument which is also known as external resistance to a setup. This is also used to control the value of the voltage supplied to a setup.