Two organ pipes of the same diameter, one closed at one end and the other open at both ends are respectively 0.75m and 1.56 m long. When sounded together, the number of beats heard is 4 per second. Find the velocity of sound in air.

Explanation

To find the velocity of sound in air using the information given about the two organ pipes, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the lengths of the pipes**:
- Length of the closed pipe (L1) = 0.75 m
- Length of the open pipe (L2) = 1.56 m

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