Chapter 10 & 11

Elasticity, Oscillations,

Waves, and Sound

Beats

Beats occur when waves of slightly different frequencies interfere.

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Standing Waves

Standing waves are formed when two waves having the same frequency, amplitude, and wavelength travel in opposite directions through a medium.

Standing waves in a string:

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Example 24

One of the harmonics on a string 1.30 m long has a frequency of 15.60 Hz. The next higher harmonic has a frequency of 23.40 Hz. Find (a) the fundamental frequency, and (b) the speed of waves on this string.

Solution:

The fundamental frequency is the difference between the given frequencies:

Find the speed:

On to Sound Part 5