What will be the effect on the fundamental frequency of a closed organ pipe if instead of air it is filled with a gas lighter than air ?

Explanation

To solve the question regarding the effect on the fundamental frequency of a closed organ pipe when filled with a gas lighter than air, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Fundamental Frequency**:
The fundamental frequency (f) of a closed organ pipe is given by the formula:
\[
f = \frac{V}{4L}
...