A : Ohm's law is universally applicable for all conducting elements.
R : All conducting show straight line graphic variation on (l-V) plot.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion , then mark
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion then mark.
C. If Assertion is ture statement but Reason is false , then mark
D. If both Assertion and Reason are false statements then mark.

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Ohm's law is universally applicable for all conducting elements."
- Ohm's law states that the current (I) through a conductor between two points is directly proportional to the voltage (V) across the two points, expressed as \( V = I \cdot R \), where R is the resistance.
- However, this law is only applicable to **Ohmic conductors**. Non-Ohmic conductors (like diodes, transistors, etc.) do not follow this law universally.
- Therefore, the assertion is **false**.

2. **Understanding the Reason (R)**:
- The reason states that "All conducting elements show straight line graphic variation on (I-V) plot."
- An I-V plot represents the relationship between current (I) and voltage (V). For Ohmic conductors, this plot is indeed a straight line, indicating a constant resistance.
- However, for non-Ohmic conductors, the I-V relationship is nonlinear, and the plot does not yield a straight line.
- Therefore, the reason is also **false**.

3. **Conclusion**:
- Since both the assertion and the reason are false, the correct answer to the question is that both statements are incorrect.

### Final Answer:
Both the assertion (A) and the reason (R) are false.

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