## Question

The air in a closed tube 34 cm long is vibrating with 2 nodes and 2 antinodes and the temperature is 51^{o}C. What is the wavelength of waves produced in air outside the tube when the temperature of air is 16^{o}C?

### Solution

32.1 cm

Since it is a closed tube and vibrating with 2 nodes and 2 antinodes, the length of the tube = λ.

Hence λ = 34

If *n* is the frequency and *v*_{51} is the velocity, then

When the outside temperature is 16^{o}C, let *v*_{16} be the velocity of sound and the wavelength.

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