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Which of the following statement is/are ...

Which of the following statement is/are correct?
I Potential difference across the terminals of a battery can be greater than its emf.
II, When current is taken from a battery. `V=E-Ir`

A

I and 11 both are correct

B

(2) I is correct and 11 Is incorrect

C

I Is Incorrect and II Is correct

D

I and 11 both are incorrect

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the two statements provided regarding the potential difference across a battery and its relationship to the electromotive force (emf). ### Step-by-Step Solution: **Step 1: Analyze Statement I** - Statement I claims that the potential difference across the terminals of a battery can be greater than its emf. - The potential difference (V) across the terminals of a battery is defined as the voltage available for external use, while the emf (E) is the maximum potential difference when no current is flowing. - In a real battery, there is internal resistance (r), and when current (I) flows, the potential difference can be expressed as: \[ V = E - I \cdot r \] - Since both I and r are positive when current is drawn from the battery, the term \(I \cdot r\) is also positive. Therefore, the potential difference V will always be less than or equal to the emf E. - Thus, Statement I is **incorrect**. **Step 2: Analyze Statement II** - Statement II states that when current is taken from a battery, \(V = E - I \cdot r\). - This equation is derived from Kirchhoff's voltage law and correctly describes the relationship between the potential difference (V), emf (E), current (I), and internal resistance (r). - When current flows, the potential difference across the terminals is indeed reduced by the voltage drop due to internal resistance. - Therefore, Statement II is **correct**. ### Conclusion: - Statement I is incorrect. - Statement II is correct. - The correct answer is that **only Statement II is correct**. ### Final Answer: - The correct option is: **Statement I is incorrect, and Statement II is correct**. ---
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