Assertion : Beat frequency between two tuning forks `a` and `B` is `4 H_(Z)` . Frequency of `A` is greater then the frequency of `B`. When `a` is loaded with wax, beat frequency may increase or decrease.
Reason : When a tuning fork is loaded with wax, its frequency decreases.

Options

A. If both Asseration and Reason are true an dthe Reason is correct explanation of the Asseration.
B. If both Asseration and Reason are true but Reason is not the correct explanation of Asseration.
C. If Asseration is true , but the Reason is false.
D. If Asseration is false but the Reason is true.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that the beat frequency between two tuning forks A and B is 4 Hz, with the frequency of A being greater than that of B. This means:
\[ f_A - f_B = 4 \, \text{Hz} \]
where \( f_A \) is the frequency of tuning fork A and \( f_B \) is the frequency of tuning fork B.

### Step 2: Analyze the Effect of Loading Tuning Fork A with Wax
When tuning fork A is loaded with wax, its frequency decreases. This can be expressed as:
\[ f_A' < f_A \]
where \( f_A' \) is the new frequency of tuning fork A after being loaded with wax.

### Step 3: Determine the New Beat Frequency
Now we have two scenarios to consider regarding the new frequency \( f_A' \):
1. **Scenario 1**: If \( f_A' \) still remains greater than \( f_B \) (i.e., \( f_A' > f_B \)), the beat frequency will decrease. The new beat frequency can be calculated as:
\[ \text{New Beat Frequency} = f_A' - f_B < 4 \, \text{Hz} \]

2. **Scenario 2**: If \( f_A' \) decreases such that it becomes less than \( f_B \) (i.e., \( f_A' < f_B \)), the beat frequency will increase. The new beat frequency can be calculated as:
\[ \text{New Beat Frequency} = f_B - f_A' > 4 \, \text{Hz} \]

### Step 4: Conclusion on the Assertion
Since the beat frequency can either decrease or increase depending on how much the frequency of A decreases after being loaded with wax, the assertion is true.

### Step 5: Analyze the Reason
The reason states that when a tuning fork is loaded with wax, its frequency decreases. This statement is also true.

### Step 6: Relationship Between Assertion and Reason
While both the assertion and reason are true, the reason does not directly explain the assertion about the beat frequency. The reason only explains the effect of loading wax on the frequency of A, but does not address the change in beat frequency directly.

### Final Conclusion
Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Answer:
The correct option is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

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