<html xmlns="http://www.w3.org/1999/xhtml"><head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
        <meta name="viewport" content="width=device-width, height=device-height, initial-scale=0.5, minimum-scale=0.5, user-scalable=yes, maximum-scale=2.0, target-densitydpi=device-dpi" />
				<meta name="robots" content="all"/>
        <meta name="description" content="description">
        <meta name="keywords" content="">
        <title>Page 30 - 11-phy-10</title>
<style type="text/css">
<!--
body {
	margin-left: 0px;
	margin-top: 0px;
	margin-right: 0px;
	margin-bottom: 0px;
}
  
#container {margin:50px auto;padding:0px;width:910px;}
#left-button{ width:90px; height:100%;float:left }
#middle{ width:730px; margin:0px; float: left;}
#right-button{ width:90px; float:left;}
html, body, div, ul, li, dl, dt, dd, h1, h2, h3, h4, h5, h6, form, input, dd,select, button, textarea, iframe, table, th, td { margin: 0; padding: 0; }
img { border: 0 none; displayblock}
span,ul,li,image{ padding:0px; margin:0px; list-style:none;}
#top-title{ width:714px; margin-bottom:10px; float:left; padding:0px 8px}
#top-title2{ width:320px;  float:right;}
#content{ width: 730px; float:left;float:left;word-wrap: break-word;}
#content-top{ width:730px; background-image:url(images/top_bg.jpg); height:56px; background-repeat:no-repeat; float:left;}
#content-top1{ width:70%; padding:16px 0px 0px 30px; font-family:Arial, Helvetica, sans-serif; font-size:24px; color:#636363;float:left;}
#content-top2{ width:60px; float:right; padding:25px 30px 0px 0px;font-family:Arial, Helvetica, sans-serif; font-size:11px; color:#2f2f2f; font-weight:bold; text-align:right}
#content-middle{ width:730px; background-image:url(images/middle_bg.jpg); background-repeat:repeat-y;float:left;}
#content-middle1{ width:475px; padding:25px 0px 25px 35px; font-family:Arial, Helvetica, sans-serif; font-size:12px; color:#636363; line-height:150%;float:left;}
#content-middle2{  padding:7px; float:right; margin:25px 35px 0px 0px; border:solid 1px #c8c8c9; background-color:#FFF; text-align:center}
#content-bottom{ width:730px; background-image:url(images/bottom_bg.jpg); background-repeat:no-repeat; height:58px;float:left;}
#content-bottom2{ width:110px; height:42px; margin:0px auto; padding-top:4px;}
#input{ width:58px; height:20px; background-color:#FFF; border:solid 1px #dfdfe0; color:#636363; text-align:center; font-size:11px;}
.font1{ font-family:Arial, Helvetica, sans-serif; font-size:10px; color:#2f2f2f;}
.font1 a:link{
	text-decoration: none;
    color:#2f2f2f;

}
.font1 a:visited{
	text-decoration: none;
    color:#2f2f2f;
	
}
.font1 a:hover{
	color: #2f2f2f;
	text-decoration: underline;

}



.text-container {
padding: 20px;
color: #333;
margin-top: 24px;
line-height: 22px;
border-top-left-radius: 3px;
border-top-right-radius: 3px;
}

.use-as-video {
float: right;
padding-left: 20px;
}
.cc-float-fix:before, .cc-float-fix:after {
content: "";
line-height: 0;
height: 0;
width: 0;
display: block;
visibility: hidden;
}
.use-as-video-img {
cursor: pointer;
position: relative;
width: 320px;
height: 180px;
}
.use-as-video-title {
font-size: 15px;
font-weight: bold;
color: #000000;
padding-bottom: 5px;
}
-->
</style>
<script type="text/javascript">
<!--
function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}
//-->
</script>
</head>

<body onload="MM_preloadImages('images/next2.png','images/previous2.png')">
<div id="container">
<div id="left-button">
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p><a href="page29.html"><img src="images/previous_big.png" width="90" height="80" /></a></p>
</div>
<div id="middle">
  <div id="top-title"><span class="font1">Basic HTML Version</span>
    <div id="top-title2">
      <table width="100%" border="0" align="right" cellpadding="0" cellspacing="0">
        <tr>
        	<td width="66%"> </td>
          <td width="35%" style="display:none" align="right"><img src="images/content.png" width="19" height="16" /></td>
          <td width="31%" style="display:none" class="font1"><a href="">Table of Contents</a></td>
          <td width="6%"><img src="images/view.png" width="19" height="16" /></td>
          <td width="28%" class="font1"><a href="../../index.html#p=30">View Full Version</a></td>
        </tr>
      </table>
    </div>
  </div>
  <div id="content">
     <div id="content-top">
        <div id="content-top1">Page 30 - 11-phy-10</div>
        <div id="content-top2">P. 30</div>
     </div>
     <div id="content-middle">
     	
     	  <div class="text-container">
    <div class="use-as-video cc-float-fix">
      <a style="text-decoration: none;" href="../../index.html#p=30"><img src="../thumb/30.jpg" /></a>
    </div>

    <p class="use-as-video-title"></p>
    <pre style="white-space:pre-line"><code>10.OPTICAL INSTRUMENTS  eLearn.Punjab

10.6   A compound microscope has lenses of focal length 1.0 cm and 3.0 cm. An object is placed
10.7   1.2 cm from the object lens. If a virtual image is formed, 25 cm from the eye, calculate the
10.8   separation of the lenses and the magnification of the instrument.
10.9
10.10                                                                                                       (Ans: 8.7 cm, 47)
       Sodium light of wavelength 589 nm is used to view an object under a microscope. If the
       aperture of the objective is 0.90 cm, (i) find the limiting angle of resolution, (ii) using visible
       light of any wavelength, what is the maximum limit of resolution for this microscope.

                                                                            [Ans: (i) 8.0 x 10-5 rad, (ii) 5.4 x 10-5 rad]
       An astronomical telescope having magnifying power of 5 consists of two thin lenses 24 cm
       apart. Find the focal lengths of the lenses.

                                                                                                         [Ans: 20 cm, 4 cm]
       A glass light pipe in air will totally internally reflect a light ray if its angle of incidence is
       at least 39Â°. What is the minimum angle for total internal reflection if pipe is in water?
       (Refractive Index of water = 1.33)

                                                                                                                      [Ans: 57Â°]
       The refractive index of the core and cladding of an optical fibre are 1.6 and 1.4 respectively.
       Calculate (i) the critical angle for the interface (ii) the maximum angle of incidence in the
       air of a ray which enters the fibre and is incident at the critical angle on the interface.

                                                                                                       [Ans: (i) 61Â°, (ii) 51Â°]

                        30

                                                                                               v: 1.1</code></pre>
     	</div>
    
     </div>
     <div id="content-bottom">
       <div id="content-bottom2">
         <table width="110" border="0" cellspacing="0" cellpadding="0">
           <tr>
             <td width="22%" height="44"><a href="page29.html"><img src="images/previous.png" width="26" height="19" id="Image2" onmouseover="MM_swapImage('Image2','','images/previous2.png',1)" onmouseout="MM_swapImgRestore()" /></a></td>
             <td width="43%">
             	&nbsp;&nbsp;&nbsp;<a href="page25.html">25</a>&nbsp;&nbsp;&nbsp;<a href="page26.html">26</a>&nbsp;&nbsp;&nbsp;<a href="page27.html">27</a>&nbsp;&nbsp;&nbsp;<a href="page28.html">28</a>&nbsp;&nbsp;&nbsp;<a href="page29.html">29</a>&nbsp;&nbsp;&nbsp;<a href="page30.html">30</a>
             </td>
             <td width="35%"><a href=""><img src="images/next.png" width="26" height="19" id="Image1" onmouseover="MM_swapImage('Image1','','images/next2.png',1)" onmouseout="MM_swapImgRestore()" /></a></td>
           </tr>
         </table>
       </div>
     </div>
  </div>
</div>
<div id="right-button">
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p>&nbsp;</p>
  <p><a href=""><img src="images/next_big.png" width="90" height="80" /></a></p>
</div>


</div>
</body>
</html>