(A) : A portable AM radio set must be kept horizontal to receive the signals properly.
(R) : Radio waves are polarised electromagnetic waves.

Options

A. Both 'A' and 'R' are true and 'R' is the correct explanation of 'A'.
B. Both 'A' and 'R' are true and 'R' is not the correct explanation of 'A'.
C. A' is true abd 'R' false
D. A' is false and 'R' is false

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided. Let's break it down step by step.

### Step 1: Analyze the Assertion (A)
The assertion states: "A portable AM radio set must be kept horizontal to receive the signals properly."

- **Understanding the Assertion**: This statement is true. Portable AM radio sets use antennas that are sensitive to the orientation of the incoming radio waves. For optimal reception, the antenna must be aligned in a specific direction, which is typically horizontal for AM radio signals.

### Step 2: Analyze the Reason (R)
The reason states: "Radio waves are polarized electromagnetic waves."

- **Understanding the Reason**: This statement is also true. Radio waves, like all electromagnetic waves, can be polarized. Polarization refers to the orientation of the electric field vector of the wave. However, not all radio waves are polarized in the same way, and the polarization of the wave does not directly explain why the AM radio set must be kept horizontal.

### Step 3: Determine the Relationship between A and R
Now, we need to assess whether the reason (R) correctly explains the assertion (A).

- **Explanation Analysis**: While both statements are true, the reason does not provide a correct explanation for the assertion. The requirement for the radio set to be horizontal is due to the sensitivity of the antenna to the magnetic component of the electromagnetic wave, not directly because radio waves are polarized.

### Conclusion
Both the assertion (A) and the reason (R) are true, but the reason does not correctly explain the assertion. Therefore, the final answer is that both A and R are true, but R is not the correct explanation of A.

### Final Answer
Both A and R are true, but R is not the correct explanation of A.

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