Waves Interact With And Other

Interactions of Waves

Objectives:

1. Place examples of reflection, refraction, diffraction, and interference.

2. Explicate some common phenomena using these concepts.

Resources:

Notes:

Interference

When two waves come up in contact with each other they interact. This interaction is described every bit interference. At that place are ii master types of interference.

A) Effective interference:

� The crests of the waves line upward (in phase)

� Results in the sum (+) of the amplitudes of the ii waves

Constructive Interference

( library.thinkquest.org/19537/ media/diagram7.gif)

B) Subversive Interference: (see pg. 507 for moving picture)

� The crests of ane wave encounter the troughs of another wave (out of phase)

� Results in the difference(-) of the amplitudes of the 2 waves

Destructive interference

Nodes & Antinodes

� The antinode is the place where maximum energy is displaced during constructive interference.

� The node is where no energy is displaced due to destructive interference

If a wave has a combination of the 2 it is chosen a standing wave. A continuing wave describes a situation where a wave is reflected so that it appears to be stationary.

(world wide web.udallas.edu/physics/ images/standi41.jpg)

The Doppler Result:

As you may accept noticed at your last trip to the racetrack, the cars engines seem to make a college pitched sound and as they pass the pitch seems to get lower. This phenomena tin can easily exist explained by the Doppler effect. This change in pitch is actually due to a change in frequency. The alter in frequency is due to the added speed of the auto.

The speed of the two vectors are not condiment
The pitch is interpreted as beingness higher do to the motion of the generator of the audio with respect to the observer.

Doppler effect diagram

(www.physicsclassroom.com/ Class/sound/u11l3b1.gif)

As you tin see the observer on the right senses an increment in frequency (higher pitch) due to the motion of the police force car while the observer on the right senses a subtract in frequency (lower pitch)

The same phenomena can be seen with low-cal. Within the visual spectrum ruby-red light has the lowest frequency and violet has the highest frequency. This phenomena is chosen bluish shift. Astronomers apply it to describe the motion of galaxies and spinning stars.

Blueshift, Redshift