# Waves, Sound and Light: Sound and Music

## Sound and Music: Audio Guided Solutions

#### Problem 27:

A musical recorder acts as an open-end air column, with a vibrational antinode located at the hole near the mouthpiece (known as the windway hole) and a vibrational antinode located at the nearest open tone hole. Blowing gently on the mouthpiece will force the air column to vibrate at its fundamental frequency. Assuming a speed of sound of 345 m/s, what length of air would be required to cause the recorder to sound out at 1050 Hz?

## Habits of an Effective Problem Solver

• Read the problem carefully and develop a mental picture of the physical situation. If necessary, sketch a simple diagram of the physical situation to help you visualize it.
• Identify the known and unknown quantities and record in an organized manner, often times they can be recorded on the diagram itself. Equate given values to the symbols used to represent the corresponding quantity (e.g., v = 345 m/s, λ = 1.28 m, f = ???).
• Use physics formulas and conceptual reasoning to plot a strategy for solving for the unknown quantity.
• Identify the appropriate formula(s) to use.
• Perform substitutions and algebraic manipulations in order to solve for the unknown quantity.