Assertion-Reason on Dry Cell EMF – Rankers Physics

Combination of Batteries: Practice Problem & Solution

Assertion (A): A larger dry cell has higher emf. Reason (R): The emf of a dry cell is proportional to its size.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Combination of Batteries. Understanding the underlying formula is key to arriving at the correct answer below:

The electromotive force (EMF) of a cell depends only on the nature of the electrodes and electrolyte, not its size. Size affects internal resistance and current capacity. Both assertion and reason are incorrect.

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