<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 12 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:"Comic Sans MS";
panose-1:3 15 7 2 3 3 2 2 2 4;}
@font-face
{font-family:Webdings;
panose-1:5 3 1 2 1 5 9 6 7 3;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Comic Sans MS";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0cm;
mso-margin-bottom-alt:auto;
margin-left:0cm;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
span.emailstyle17
{mso-style-name:emailstyle17;
font-family:"Arial","sans-serif";
color:windowtext;}
span.EmailStyle21
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page Section1
{size:21.0cm 842.0pt;
margin:2.0cm 72.0pt 2.0cm 72.0pt;}
div.Section1
{page:Section1;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang=EN-NZ link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>Hi
Francis<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>I
have just tried a similar expt with a glass mug (school issue!!) – I get
the opposite result – used a simple FFT application to see the
frequencies etc. Bizarre!!<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>I
remember a similar expt presented in Jearl Walker’s book “The
flying circus of physics” in which he asks why the frequency changes (while
tapping on the side of the cup) during the process of adding instant coffee or
milk to hot water. I believe this is due to a change in velocity (due to
air-filled water having a lower speed of sound than the non airfilled).
Maybe this would be a good IYPT problem??<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>Cheers<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>David<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'>
<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> phys-teach-talk-bounces@nzip.org.nz
[mailto:phys-teach-talk-bounces@nzip.org.nz] <b>On Behalf Of </b>Bryden,
Francis<br>
<b>Sent:</b> Monday, 30 June 2008 2:44 p.m.<br>
<b>To:</b> phys-teach-talk@nzip.org.nz<br>
<b>Subject:</b> <o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<div>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif"'>When
you tap a glass beaker with a spoon you get a high frequency sound. </span><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Can
anyone explain why the frequency drops when you pour in water</span><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif"'> </span><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Thanks
<em><span style='font-family:"Arial","sans-serif"'>................ Francis</span></em></span><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>Francis Bryden</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>HoD Physics</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>St Cuthbert's College</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>122 Market
Rd
or Box 26 020</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>Epsom Epsom</span></em><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>Auckland
1051
Auckland 1344</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>New
Zealand New
Zealand</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p>
<p class=MsoNormal><em><span lang=EN-US style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>ph: 64 9 5204159 ext 7808</span></em><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif"'><a
href="mailto:fbryden@stcuthberts.school.nz"><em><span style='font-family:"Arial","sans-serif";
color:windowtext;text-decoration:none'>fbryden@stcuthberts.school.nz</span></em></a></span><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> <o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span lang=EN-US style='font-size:12.0pt;font-family:"Times New Roman","serif"'> </span><strong><span
style='font-family:Webdings;color:green'>P </span></strong><strong><span
style='font-size:7.5pt;font-family:"Verdana","sans-serif";color:green'>Please
consider the environment before printing this email</span></strong><span
lang=EN-US style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
</div>
<div>
<div class=MsoNormal align=center style='text-align:center'><span lang=EN-US
style='font-size:12.0pt;font-family:"Times New Roman","serif"'>
<hr size=2 width="100%" align=center>
</span></div>
</div>
<div>
<p class=MsoNormal style='margin-bottom:12.0pt'><span lang=EN-US
style='font-size:10.0pt;font-family:"Times New Roman","serif"'>This message
(and any associated files) is intended only for the <br>
use of the individual or entity to which it is addressed and may <br>
contain information that is confidential, subject to copyright or<br>
constitutes a trade secret. If you are not the intended recipient <br>
you are hereby notified that any dissemination, copying or <br>
distribution of this message, or files associated with this message, <br>
is strictly prohibited. If you have received this message in error, <br>
please notify us immediately by replying to the message and deleting <br>
it from your computer. Messages sent to and from us may be monitored.</span><span
lang=EN-US style='font-size:9.0pt;font-family:"Courier New"'> <o:p></o:p></span></p>
<div class=MsoNormal align=center style='text-align:center'><span lang=EN-US
style='font-size:9.0pt;font-family:"Courier New"'>
<hr size=2 width="100%" align=center>
</span></div>
</div>
<p class=MsoNormal><span lang=EN-US style='font-size:7.5pt;font-family:"Times New Roman","serif"'>This
email has been checked by Symantec Mail Security for Exchange. 14:43:30 Mon 30
Jun 2008 </span><span lang=EN-US style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>No virus
found in this incoming message.<br>
Checked by AVG.<br>
Version: 8.0.101 / Virus Database: 270.4.3/1525 - Release Date: 29/06/2008 3:09
p.m.</span><o:p></o:p></p>
</div>
</body>
</html>