Question

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Net charge within a conductor is always zero. Reason (R): The conductor has a very large number of free electrons. In the light of the above statements, choose the most appropriate answer from the options given below :

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is not correct
• D. (A) is not correct but (R) is correct

Hint:

In electrostatic equilibrium:
• Electric field inside conductor is zero.
• Excess charges reside on surface.

Answer 1

The Correct Option is B

Concept: In electrostatic equilibrium:
• Electric field inside a conductor becomes zero.
• Excess charges reside on conductor surface. A conductor contains:
• Large number of free electrons but this alone does not explain why net charge becomes zero.

Step 1: Analyze Assertion (A). Assertion states: Net charge within a conductor is always zero. In electrostatic equilibrium:
• Excess charge shifts to outer surface.
• Interior of conductor remains electrically neutral. Hence: \[ (A)\text{ is correct} \]

Step 2: Analyze Reason (R). Reason states: The conductor has a very large number of free electrons. This statement is also true. Conductors indeed contain many free electrons responsible for electrical conduction. Thus: \[ (R)\text{ is correct} \]

Step 3: Check whether Reason explains Assertion. Although free electrons exist:
• Their presence alone does not directly explain charge neutrality.
• Charge neutrality results from redistribution of charges under electrostatic equilibrium. Hence:
• Both statements are true.
• But Reason is not the correct explanation of Assertion.

Step 4: Write the final answer. Therefore, the correct option is: \[ \boxed{(B)\ \text{Both (A) and (R) are correct but (R) is not the correct explanation of (A)}} \]