|
|
|
|
Noise cancellation demo setup. ASU copyright An FM radio is tuned to a vacant channel. ASU copyright Adjust volume using the Master Volume control. ASU copyright Demo works best with speaker covers removed. ASU copyright Position speakers facing each other and close together. ASU copyright To put the speakers out of phase, reverse the cable polarity to one speaker ASU copyright Connections on the back of the amplifier. ASU copyright
    |
.jpg) .jpg) .jpg) .jpg) .jpg) .jpg)  |
PHYSICS |
||
| 3B55.101 | Noise Cancellation | Rating: |
||
|
Captions and Credits to the left in the sidebar. |
||||
|
Description: An Fm radio is tuned to a vacant channel, so that only white noise is heard. The output of the radio is then connected to an amplifier which in turn is connected to two speakers. With the speakers connected in phase they are positioned facing each other and close together. When the cable polarity of one speaker is reversed, the speakers are no longer in phase the sound level is dramatically reduced. |
||||
| Room:PS F175 | Location: Bd2, Dc2, 0_3 | Sublocation: | ||
| Type: demo | Date Added:5/12/2006 | Condition: | ||
| Quantity:1 | Complete: | Last updated: | ||
| Purpose: | ||||
| Safety Issues: Disclaimer (Warning - work in progress - may be incomplete) | ||||
| Equipment Issues: | ||||
| Parts: FM radio, matching speakers, Realistic amplifier, and cables | ||||
| Copyright © 2000 | Instructions:The output of an FM radio tuned to a vacant channel and is connected to the AUX input or our Realistic amplifier. Two speakers are connected to the amplifier's 8 ohm output making sure that the polarity is the same for both speakers. It is best to adjust the volume using only the Master Volume control on the amplifier. The radio's volume and the AUX and Equalizer slider controls sould be at maximum. With the radio already tuned to a vacant channel, the instructor adjusts the volume to an appropriate level. The speakers, which are initially facing the class, are then turned towards each othe and put very close together. The sound from the speakers is then put out of phase switching the polarity of the cables connected to one speaker. Dramatically the sound is reduced. While still out of phase the instructor should gradually rotate the speakers towards the class. A sound similar to the roar of a jet engine can be heard as first higher frequencies (shorter wavelengths) and then lower ones escape cancellation. | |||
| Arizona Board of Regents | Notes: | |||
| Webmaster Privacy | ||||
| Accessibility | References: | |||
 |
Links: | Movie: | Caption: | |
 |
|
|
| 1A0 | MEASUREMENT |
 |
||
| 1A10 | Basic Units |
|
||
| 1A10.10 | Basic units set-Video | Video Encyclopedia: Show a clock with a second sweep, meter & yard sticks, and kilogram and pound mass |
VE01_01
|
 |
|
3_1
|
||||
|
PS F175
|
||||
| 1A10.35 | Meter stick - 4 sided | Graduated in meters, decimeters, centimeters, & millimeters |
.jpg) |
|
|
Aa2
|
||||
|
PS F175
|
||||
| 1A10.50 | Liter Cube/set |
.jpg) |
||
|
Aa2
|
||||
|
PS F175
|
||||
| 1A10.510 | Meter Cube | Meter cube frame, stored dismantled |
.jpg) |
|
|
Aa2
|
||||
|
PS F175
|
||||
| 1A10.520 | Volume Perception Paradox | One liter of colored water is poured from a sphere to cylinder. The sphere seems smaller but is of equal volume. |
.jpg) |
|
|
PS F175
|
||||
| 1A10.60 | Avogadro's Number box | Black 22.4 liter cube |
.jpg) |
|
|
Aa2
|
||||
|
PS F175
|
||||
| 1A20 | Error and Accuracy |
|
||
|
|
||||
| 1A20.10 | Gaussian curve - Video | Video Encyclopedia: A commercial device for the overhead projector where ball bearings roll through an array of nails into parallel chutes. |
VE16_12
|
 |
|
3_1
|
||||
|
PS F175
|
||||
| 1A20.25A | Dice - ordinary |
.jpg) |
||
|
Aa2
|
||||
|
PS F175
|
||||
| 1A20.25B | Dice - overhead |
.jpg) |
||
|
Aa2
|
||||
|
PS F175
|
||||
| 1A20.25C | Dice - polyhedral |
.jpg) |
||
|
Aa2
|
||||
|
PS F175
|
||||
| 1A20.25D | Dice - large foam |
.jpg) |
||
|
Aa2
|
||||
|
PS F175
|
||||
| 1A30 | Coordinate System |
|
||
|
|
||||
| 1A30.10A | XYZ Coordinate axes | Long arrow shafts with label attachments |
top
|
.jpg) |
|
7
|
||||
|
PS F175
|
||||
| 1A30.10B | XYZ Coordinate axes | Zometool version |
.jpg) |
|
|
Aa3
|
||||
|
PS F175
|
||||
| 1A30.10C | XYZ Coordinate axes | Medium arrow shafts with dull broadheads |
.jpg) |
|
|
cabinet
|
||||
|
PS H356
|
||||
| 1A30.30 | Polar Coordinates | A semi circle is rotated about an axis to demonstrate why integration over theta is from zero to 180 degrees. |
.jpg) |
|
|
Aa3
|
||||
|
PS F175
|
||||
| 1A30.30 | Polar Coordinates |
|
||
| 1A30.40A | Chalkboard Globe - Large |
.jpg) |
||
|
Af6
|
||||
|
PS H156
|
||||
| 1A30.40B | Chalkboard Globe - Small |
.jpg) |
||
|
Af6
|
||||
|
PS H156
|
||||
| 1A40 | Vectors |
|
||
|
|
||||
| 1A40.001 | Vector models, Magnetic Field model, Electric Field model, Electromagnetic Field model | Three cardboard vector models. 1) A uniform vector field represented by 9 arrows in 3 by 3 array. 2)Single vector represent by an arrow perpendicular to cardboard. 3) Same as 2) except a circle is drawn around the arrow to represent the curl of the vector |
.jpg) |
|
|
Aa3
|
||||
|
PS F175
|
||||
| 1A40.10 | Vector components (3D)-Video | Video Encyclopedia : Metal arrows define a three dimensional coordinate system. An arbitrary vector is viewed in three planes. |
VE01_07
|
 |
|
3_1
|
||||
|
PS F175
|
Records 1 to 25 of 1978
|
|
|
.jpg)