Question

The number of possible natural oscillations of the air column in a pipe closed at one end of length 85 cm whose frequencies lie below 1250 Hz? (v = 340 m/s)

Options

• 3

• 4

• 5

• 6

Answer 1

6

Explanation:

f₀ = `"V"_"s"/(4ℓ_0)`

= `340/(4 xx 85 xx 10^-2)`

f₀ = 100 Hz

Only odd harmonics are produced.

100 Hz, 300 Hz, 500 Hz, 700 Hz, 900 Hz, 1100 Hz