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Assertion: For good conductors, the I-V ...

Assertion: For good conductors, the I-V graph is a perfect straight line inclined to current axis.
Reason: By Ohm's law, voltage across the ends of a conductor is directly proportional to the resistance of the conductor.

A

If both assertion and reason are true and reason is the correct explantion of assertion.

B

If both assertion and reason are true and reason is not the correct explantion of assertion.

C

If assertion is false but reason is true.

D

If assertion is true but reason is false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion-reason question, we will analyze both the assertion and the reason separately. ### Step 1: Analyze the Assertion The assertion states: "For good conductors, the I-V graph is a perfect straight line inclined to the current axis." - **Understanding the Assertion**: - In an I-V (current-voltage) graph, if the relationship between current (I) and voltage (V) is linear, it indicates that the conductor follows Ohm's Law. - For good conductors, the I-V graph is indeed a straight line, which means that the voltage across the conductor is directly proportional to the current flowing through it. - This is characteristic of ohmic materials, where the slope of the line represents the resistance (R) of the conductor. **Conclusion for Assertion**: The assertion is **correct**. ### Step 2: Analyze the Reason The reason states: "By Ohm's law, voltage across the ends of a conductor is directly proportional to the resistance of the conductor." - **Understanding the Reason**: - Ohm's Law states that V = IR, where V is the voltage, I is the current, and R is the resistance. - According to Ohm's Law, the voltage (V) across a conductor is directly proportional to the current (I) flowing through it, not directly proportional to the resistance (R). - The correct interpretation of Ohm's Law is that for a given resistance, if the voltage increases, the current also increases proportionally. **Conclusion for Reason**: The reason is **incorrect**. ### Final Conclusion - The assertion is correct while the reason is incorrect. Therefore, the final answer is that the assertion is true, and the reason is false. ---
To solve the assertion-reason question, we will analyze both the assertion and the reason separately. ### Step 1: Analyze the Assertion The assertion states: "For good conductors, the I-V graph is a perfect straight line inclined to the current axis." - **Understanding the Assertion**: - In an I-V (current-voltage) graph, if the relationship between current (I) and voltage (V) is linear, it indicates that the conductor follows Ohm's Law. - For good conductors, the I-V graph is indeed a straight line, which means that the voltage across the conductor is directly proportional to the current flowing through it. ...
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