Sometimes, when the wind blows across a long wire, a low-frequency "moaning" sound is produced. The sound arises because a standing wave is set up on the wire, like a standing wave on a guitar string. Assume that a wire (linear density = 0.0120 kg / m) sustains a tension of 341 N because the wire is stretched between two poles that are 16.86 m apart. The lowest frequency that an average, healthy human ear can detect is 20.0 Hz. What is the lowest harmonic number n that could be responsible for the "moaning" sound?

Answer is not n = 4.47

Question

Bridges

Physics

16 December, 07:45

Sometimes, when the wind blows across a long wire, a low-frequency "moaning" sound is produced. The sound arises because a standing wave is set up on the wire, like a standing wave on a guitar string. Assume that a wire (linear density = 0.0120 kg / m) sustains a tension of 341 N because the wire is stretched between two poles that are 16.86 m apart. The lowest frequency that an average, healthy human ear can detect is 20.0 Hz. What is the lowest harmonic number n that could be responsible for the "moaning" sound?

Answer is not n = 4.47

+4

Answers (1)

Know the Answer?

Cristian Barry · Answer 1

The smallest integer is n = 4

Explanation:

Using the equation V = Sqrt (F/Linear density)

V = Sqrt (341/0.0120)

V = Sqrt (28416.7)

V = 168.57m/s

Path distance = [ (n + 1) / 2]lambda

But V = f (Lambda)

n lambda/2 = L

n = f2L/V

n = (20 * 2 * 16.86) / 168.57

n = 4.0007

The smallest integer is n = 4