e39465ad2f
new file: Files/flashplayer_32_sa.exe
new file: favicon.ico
new file: globe.gif
new file: imgs/download.png
new file: imgs/zuck.jpg
new file: index.html
new file: other.ico
new file: script.js
new file: site.webmanifest
new file: sitemap.html
new file: styles/backround.css
new file: styles/border.css
new file: styles/fonts/Titillium_Web/OFL.txt
new file: styles/fonts/Titillium_Web/TitilliumWeb-Black.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-Bold.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-BoldItalic.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-ExtraLight.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-ExtraLightItalic.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-Italic.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-Light.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-LightItalic.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-Regular.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-SemiBold.ttf
new file: styles/fonts/Titillium_Web/TitilliumWeb-SemiBoldItalic.ttf
new file: styles/fonts/webfontkit-20221027-163353/generator_config.txt
new file: styles/fonts/webfontkit-20221027-163353/specimen_files/grid_12-825-55-15.css
new file: styles/fonts/webfontkit-20221027-163353/specimen_files/specimen_stylesheet.css
new file: styles/fonts/webfontkit-20221027-163353/stylesheet.css
new file: styles/fonts/webfontkit-20221027-163353/titilliumweb-extralight-demo.html
new file: styles/fonts/webfontkit-20221027-163353/titilliumweb-extralight-webfont.woff
new file: styles/fonts/webfontkit-20221027-163353/titilliumweb-extralight-webfont.woff2
new file: styles/fonts/webfontkit-20221027-165950/generator_config.txt
new file: styles/fonts/webfontkit-20221027-165950/specimen_files/grid_12-825-55-15.css
new file: styles/fonts/webfontkit-20221027-165950/specimen_files/specimen_stylesheet.css
new file: styles/fonts/webfontkit-20221027-165950/stylesheet.css
new file: styles/fonts/webfontkit-20221027-165950/titilliumweb-bold-demo.html
new file: styles/fonts/webfontkit-20221027-165950/titilliumweb-bold-webfont.woff
new file: styles/fonts/webfontkit-20221027-165950/titilliumweb-bold-webfont.woff2
new file: styles/style.css
new file: tools/2048/.gitignore
new file: tools/2048/.jshintrc
new file: tools/2048/CONTRIBUTING.md
new file: tools/2048/LICENSE.txt
new file: tools/2048/README.md
new file: tools/2048/Rakefile
new file: tools/2048/favicon.ico
new file: tools/2048/index.html
new file: tools/2048/js/animframe_polyfill.js
new file: tools/2048/js/application.js
new file: tools/2048/js/bind_polyfill.js
new file: tools/2048/js/classlist_polyfill.js
new file: tools/2048/js/game_manager.js
new file: tools/2048/js/grid.js
new file: tools/2048/js/html_actuator.js
new file: tools/2048/js/keyboard_input_manager.js
new file: tools/2048/js/local_storage_manager.js
new file: tools/2048/js/tile.js
new file: tools/2048/meta/apple-touch-icon.png
new file: tools/webretro/cores/neocd_libretro.js
new file: tools/webretro/cores/neocd_libretro.wasm
new file: tools/webretro/cores/nestopia_libretro.js
new file: tools/webretro/cores/nestopia_libretro.wasm
new file: tools/webretro/cores/o2em_libretro.js
new file: tools/webretro/cores/o2em_libretro.wasm
new file: tools/webretro/cores/opera_libretro.js
new file: tools/webretro/cores/opera_libretro.wasm
162 lines
7.2 KiB
HTML
162 lines
7.2 KiB
HTML
<!doctype html>
|
|
<html lang="en"><!-- #BeginTemplate "/Templates/Main.dwt" --><!-- DW6 -->
|
|
|
|
<!-- Mirrored from www.mathsisfun.com/measure/estimate-distance.html by HTTrack Website Copier/3.x [XR&CO'2014], Sat, 29 Oct 2022 00:58:04 GMT -->
|
|
<head>
|
|
<!-- #BeginEditable "doctitle" -->
|
|
<title>Estimate Distance</title>
|
|
<script language="JavaScript" type="text/javascript">reSpell=[["meters","metres"]];</script>
|
|
<meta name="description" content="Math explained in easy language, plus puzzles, games, quizzes, worksheets and a forum. For K-12 kids, teachers and parents." />
|
|
<!-- #EndEditable -->
|
|
<meta name="keywords" content="math, maths, mathematics, school, homework, education">
|
|
<meta http-equiv="content-type" content="text/html; charset=utf-8">
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
|
|
<meta name="HandheldFriendly" content="true">
|
|
<meta http-equiv="pics-label" content='(PICS-1.1 "http://www.classify.org/safesurf/" L gen true for "http://www.mathsisfun.com" r (SS~~000 1))'>
|
|
<link rel="stylesheet" type="text/css" href="../style3.css" />
|
|
<script src="../main3.js" type="text/javascript"></script>
|
|
</head>
|
|
|
|
<body id="bodybg">
|
|
<div class="bg">
|
|
<div id="stt"></div>
|
|
<div id="hdr"></div>
|
|
<div id="logo"><a href="../index.html"><img src="../images/style/logo.svg" alt="Math is Fun" /></a></div>
|
|
<div id="gtran"><script type="text/javascript">document.write(getTrans());</script></div>
|
|
<div id="gplus"><script type="text/javascript">document.write(getGPlus());</script></div>
|
|
<div id="adTopOuter" class="centerfull noprint">
|
|
<div id="adTop">
|
|
<script type="text/javascript">document.write(getAdTop());</script>
|
|
</div>
|
|
</div>
|
|
<div id="adHide">
|
|
<div id="showAds1"><a href="javascript:showAds()">Show Ads</a></div>
|
|
<div id="hideAds1"><a href="javascript:hideAds()">Hide Ads</a><br>
|
|
<a href="../about-ads.html">About Ads</a></div>
|
|
</div>
|
|
<div id="menuWide" class="menu">
|
|
<script type="text/javascript">document.write(getMenu(0));</script>
|
|
</div>
|
|
<div id="linkto">
|
|
<div id="linktort"><script type="text/javascript">document.write(getLinks());</script></div>
|
|
</div>
|
|
<div id="search" role="search"><script type="text/javascript">document.write(getSearch());</script></div>
|
|
<div id="menuSlim" class="menu">
|
|
<script type="text/javascript">document.write(getMenu(1));</script>
|
|
</div>
|
|
<div id="menuTiny" class="menu">
|
|
<script type="text/javascript">document.write(getMenu(2));</script>
|
|
</div>
|
|
<div id="extra"></div>
|
|
</div>
|
|
<div id="content" role="main"><!-- #BeginEditable "Body" -->
|
|
<h1 class="center">Estimate How Far Away</h1>
|
|
<p>Here is a clever method to estimate how far away something is:</p>
|
|
<ul>
|
|
<li>Hold your arm straight out, thumb up</li>
|
|
<li>Close one eye, align your thumb with distant object</li>
|
|
<li>Switch eyes (don't move your thumb!)</li>
|
|
<li>Your thumb will seem to change position</li>
|
|
</ul>
|
|
<p>Now ... estimate how far it moved sideways (you could imagine the length of a car or something). </p><p><b>Multiply that by 10</b> and you have an estimate of how far away. </p>
|
|
<div class="example">
|
|
|
|
<p style="float:left; margin: 0 10px 5px 0;"> </p>
|
|
<p style="float:left; margin: 0 10px 5px 0;"><img src="images/thumb-distance.gif" width="243" height="209" alt="thumb distance" /></p>
|
|
<h3>Example</h3>
|
|
<p>Here your thumb seems to jump about <b>half a car length</b>. </p>
|
|
<p>Half a car length is about <b>2.5 meters</b>.</p>
|
|
<p>Times 10: the car is <b>about 25 meters away</b>.</p>
|
|
|
|
</div>
|
|
<h2>How it Works</h2>
|
|
<p style="float:right; margin: 0 0 5px 10px;"><img src="images/thumb-distance-top.gif" width="300" height="175" alt="thumb distance is 10x eye distance" /></p>
|
|
<p> </p>
|
|
<p>The distance from your <b>eyes to your thumb</b> is about 10 times the distance <b>between your eyes</b></p>
|
|
<div style="clear:both"></div>
|
|
<p style="float:left; margin: 0 20px 5px 0;"><img src="images/thumb-distance-far.gif" width="360" height="144" alt="thumb distance far" /></p>
|
|
<p> </p>
|
|
<p>And so the distance <b>to the far object</b> is also about 10 times the <b>width your thumb seems to move at the far object</b>.</p>
|
|
<p class="center"> </p>
|
|
<p class="center"><img src="images/thumb-distance-similar.svg" alt="thumb distance similar angles" /></p>
|
|
<p class="center">This works because the <a href="../geometry/triangles-similar.html">triangles are similar</a>, <br>
|
|
and so the relative lengths are the same.</p>
|
|
<div style="clear:both"></div>
|
|
<h2>Learn the Size of Things</h2>
|
|
<p>To be useful you need to know how long, wide or tall things are!</p>
|
|
<ul>
|
|
<li>Small cars are 4 m long</li>
|
|
<li>Large cars are 5 m long</li>
|
|
<li>Cars are about 1.8 m wide</li>
|
|
<li>Adults are about 1.8 m tall</li>
|
|
<li>A 5 year old is about 1 m tall</li>
|
|
<li>A normal doorway is 2 m high and 0.8 m wide</li>
|
|
<li>A truck and trailer is about 20 m long</li>
|
|
<li>The width of a small house is about 8 m </li>
|
|
<li>The width of a large house is about 12 m </li>
|
|
<li>The height of a single-storey house is about 5 m</li>
|
|
<li>The height of a two-storey house is about 8 m </li>
|
|
<li>Tall buildings have about 3.5 m for every storey</li>
|
|
</ul>
|
|
<p>(Note: to use this method for height, tilt your head and thumb 90° to the side.)</p>
|
|
<h2>Your Turn</h2>
|
|
<p>Go outside and stand on a high spot where you can see lots of things (roads, building, etc).</p>
|
|
<p>Write down what you see and estimate how far away:</p>
|
|
<div class="beach">
|
|
<table width="100%">
|
|
<tr>
|
|
<th width="60%">Object</th>
|
|
<th width="20%" align="center">"Thumb move"<br>
|
|
Distance</th>
|
|
<th width="20%" align="center">×10 = <br>
|
|
How Far Away</th>
|
|
</tr>
|
|
<tr>
|
|
<td> </td>
|
|
<td align="center"> </td>
|
|
<td align="center"> </td>
|
|
</tr>
|
|
<tr>
|
|
<td> </td>
|
|
<td align="center"> </td>
|
|
<td align="center"> </td>
|
|
</tr>
|
|
<tr>
|
|
<td> </td>
|
|
<td align="center"> </td>
|
|
<td align="center"> </td>
|
|
</tr>
|
|
<tr>
|
|
<td> </td>
|
|
<td align="center"> </td>
|
|
<td align="center"> </td>
|
|
</tr>
|
|
<tr>
|
|
<td> </td>
|
|
<td align="center"> </td>
|
|
<td align="center"> </td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<p>Bonus Activity: Get a map, mark where you stood and where each object is, and work out how far away they really are. How good were you?</p>
|
|
<p> </p>
|
|
<div class="related">
|
|
<a href="metric-length.html">Metric Length</a><a href="index.html">Measurement Index</a>
|
|
</div>
|
|
<!-- #EndEditable --></div>
|
|
<div id="adend" class="centerfull noprint">
|
|
<script type="text/javascript">document.write(getAdEnd());</script>
|
|
</div>
|
|
<div id="footer" class="centerfull noprint">
|
|
<script type="text/javascript">document.write(getFooter());</script>
|
|
</div>
|
|
<div id="copyrt">
|
|
Copyright © 2017 MathsIsFun.com
|
|
</div>
|
|
|
|
<script type="text/javascript">document.write(getBodyEnd());</script>
|
|
</body>
|
|
<!-- #EndTemplate -->
|
|
<!-- Mirrored from www.mathsisfun.com/measure/estimate-distance.html by HTTrack Website Copier/3.x [XR&CO'2014], Sat, 29 Oct 2022 00:58:05 GMT -->
|
|
</html>
|