5.1.4 Interference, Standing Waves, & Resonance

5.1.2 Interference, Standing Waves, & Resonance

​•INTERFERENCE – the result of two waves meeting in a medium.

–CONSTRUCTIVE – results in greater amplitude.

–DESTRUCTIVE – results in lower amplitude.

–Superpositioning

•

•“In phase” interferes CONSTRUCTIVELY

​

​

•“180° out of phase” interferes DESTRUCTIVELY

–

​

Multiple Choice

• A

• B

• C

• D

​Jump to slides 5-8 on ppt

​

Multiple Choice

• 2

• 3

• 4

• 6

​Phenomenon #4 - Resonance

​All mediums have a NATURAL FREQUENCY that corresponds to their atomic structure.

​

Exciting this frequency causes large AMPLITUDE vibrations in the medium

​

If the frequency is excited with enough ENERGY the medium may become damaged or even shatter.

​

If two materials have the same (or close) natural frequencies then vibrations may be passed from one material into the other.

EX. Blowing across an empty bottle

​Jump to slides 11-16 on ppt

​

Draw

Practice in notes. Sketch the standing waves, draw a circle around each ANTINODE, determine the wavelength, calculate its frequency and period.

Multiple Choice

•The diagram represents two identical pulses approaching each other in a uniform medium. As the pulses meet and are superposed, the maximum displacement of the medium is

• -6 cm

• 0 cm

• 3 cm

• 6 cm

Multiple Choice

•The diagram shows a periodic wave. Which two points on the wave are 180o out of phase?

• A and C

• B and E

• F and G

• D and H

Multiple Choice

•The diagram represents a standing wave. The number of nodes and antinodes shown in the diagram is

• 4 nodes and 5 antinodes

• 5 nodes and 6 antinodes

• 6 nodes and 5 antinodes

• 6 nodes and 10 antinodes

Multiple Choice

Glass may shatter when exposed to sound of a particular frequency. This phenomenon is an example of

• refraction

• diffraction

• resonance

• the Doppler effect