VISUAL PHYSICS ONLINE

3.1 WAVES

P31 012

You play a single note on a trombone. How do you play another note on the instrument which produces:

(A)

A louder sound?

(B)

A higher pitch note?

View solution below only after you have completed answering the question. The solution is not in a form that you would answer in an examination. The answers are often in more detail to help improve your appreciation and understanding of the physics.

Solution

Knowledge brass instruments

Visualise the problem (image a picture of a trombone). Often knowing the equation applicable to the situation can help you answer a question.

(A)

A louder sound is produced by creating a wave of larger amplitude by blowing more vigorously.

(B)

Pitch relates to the frequency of the sound. A wave of greater frequency can be produced by:

(1) Reducing the length L of the pipe.

(2) Blowing the trombone in such a way as to excite the higher harmonics (greater m value).