File "markSceme-HL-paper3.html"
Path: /IB QUESTIONBANKS/5 Fifth Edition - PAPER/HTML/Physics/Topic 7 HTML/markSceme-HL-paper3html
File size: 6.84 KB
MIME-type: text/html
Charset: utf-8
<!DOCTYPE html>
<html>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<head>
<meta charset="utf-8">
<title>IB Questionbank</title>
<link rel="stylesheet" media="all" href="css/application-02ef852527079acf252dc4c9b2922c93db8fde2b6bff7c3c7f657634ae024ff1.css">
<link rel="stylesheet" media="print" href="css/print-6da094505524acaa25ea39a4dd5d6130a436fc43336c0bb89199951b860e98e9.css">
<script src="js/application-9717ccaf4d6f9e8b66ebc0e8784b3061d3f70414d8c920e3eeab2c58fdb8b7c9.js"></script>
<script type="text/javascript" async src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js?config=TeX-MML-AM_CHTML-full"></script>
<!--[if lt IE 9]>
<script src='https://cdnjs.cloudflare.com/ajax/libs/html5shiv/3.7.3/html5shiv.min.js'></script>
<![endif]-->
<meta name="csrf-param" content="authenticity_token">
<meta name="csrf-token" content="iHF+M3VlRFlNEehLVICYgYgqiF8jIFlzjGNjIwqOK9cFH3ZNdavBJrv/YQpz8vcspoICfQcFHW8kSsHnJsBwfg==">
<link href="favicon.ico" rel="shortcut icon">
</head>
<body class="teacher questions-show">
<div class="navbar navbar-fixed-top">
<div class="navbar-inner">
<div class="container">
<div class="brand">
<div class="inner"><a href="http://ibo.org/">ibo.org</a></div>
</div>
<ul class="nav">
<li>
<a href="../../../../../../../index.html">Home</a>
</li>
<!-- - if current_user.is_language_services? && !current_user.is_publishing? -->
<!-- %li= link_to "Language services", tolk_path -->
</ul>
<ul class="nav pull-right">
<li class="dropdown">
<a class="dropdown-toggle" data-toggle="dropdown" href="#">
Help
<b class="caret"></b>
</a>
<ul class="dropdown-menu">
<li><a href="https://questionbank.ibo.org/video_tour?locale=en">Video tour</a></li>
<li><a href="https://questionbank.ibo.org/instructions?locale=en">Detailed instructions</a></li>
<li><a target="_blank" href="https://ibanswers.ibo.org/">IB Answers</a></li>
</ul>
</li>
<li>
<a href="https://06082010.xyz">IB Documents (2) Team</a>
</li></ul>
</div>
</div>
</div>
<div class="page-content container">
<div class="row">
<div class="span24">
<div class="pull-right screen_only"><a class="btn btn-small btn-info" href="https://questionbank.ibo.org/updates?locale=en">Updates to Questionbank</a></div>
<p class="muted language_chooser">
User interface language:
<a href="https://questionbank.ibo.org/en/users/set_user_locale?new_locale=en">English</a>
|
<a href="https://questionbank.ibo.org/en/users/set_user_locale?new_locale=es">Español</a>
</p>
</div>
</div>
<div class="page-header">
<div class="row">
<div class="span16">
<p class="back-to-list">
</p>
</div>
<div class="span8" style="margin: 0 0 -19px 0;">
<img style="width: 100%;" class="qb_logo" src="https://mirror.ibdocs.top/qb.png" alt="Ib qb 46 logo">
</div>
</div>
</div>
<h2>HL Paper 3</h2><div class="specification">
<p>A positive pion decays into a positive muon and a neutrino.</p>
<p><span class="mjpage mjpage__block"><math xmlns="http://www.w3.org/1998/Math/MathML" display="block" alttext="{\pi ^ + } \to {\mu ^ + } + {v_\mu }">
<mrow>
<msup>
<mi>π<!-- π --></mi>
<mo>+</mo>
</msup>
</mrow>
<mo stretchy="false">→<!-- → --></mo>
<mrow>
<msup>
<mi>μ<!-- μ --></mi>
<mo>+</mo>
</msup>
</mrow>
<mo>+</mo>
<mrow>
<msub>
<mi>v</mi>
<mi>μ<!-- μ --></mi>
</msub>
</mrow>
</math></span></p>
<p>The momentum of the muon is measured to be 29.8 MeV c<sup>–1</sup> in a laboratory reference frame in which the pion is at rest. The rest mass of the muon is 105.7 MeV c<sup>–2</sup> and the mass of the neutrino can be assumed to be zero.</p>
</div>
<div class="specification">
<p>For the laboratory reference frame</p>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p>write down the momentum of the neutrino.</p>
<div class="marks">[1]</div>
<div class="question_part_label">a.i.</div>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p>show that the energy of the pion is about 140 MeV.</p>
<div class="marks">[2]</div>
<div class="question_part_label">a.ii.</div>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p>State the rest mass of the pion with an appropriate unit.</p>
<div class="marks">[1]</div>
<div class="question_part_label">b.</div>
</div>
<h2 style="margin-top: 1em">Markscheme</h2>
<div class="question" style="padding-left: 20px;">
<p><strong>«</strong>–<strong>»</strong>29.8 <strong>«</strong>MeVc<sup>–1</sup><strong>»</strong></p>
<p><em><strong>[1 mark]</strong></em></p>
<div class="question_part_label">a.i.</div>
</div>
<div class="question" style="padding-left: 20px;">
<p><em>E<sub>π</sub></em> = <span class="mjpage"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="\sqrt {p_\mu ^2{c^2} + m_\mu ^2{c^4}} ">
<msqrt>
<msubsup>
<mi>p</mi>
<mi>μ</mi>
<mn>2</mn>
</msubsup>
<mrow>
<msup>
<mi>c</mi>
<mn>2</mn>
</msup>
</mrow>
<mo>+</mo>
<msubsup>
<mi>m</mi>
<mi>μ</mi>
<mn>2</mn>
</msubsup>
<mrow>
<msup>
<mi>c</mi>
<mn>4</mn>
</msup>
</mrow>
</msqrt>
</math></span> + <em>p<sub>v</sub>c</em> <strong><em>OR</em></strong> <em>E<sub>μ</sub></em> = 109.8 <strong>«</strong>MeV<strong>»</strong></p>
<p><em>E<sub>π</sub></em> = <strong>«</strong><span class="mjpage"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="\sqrt {{{29.8}^2} + {{105.7}^2}} ">
<msqrt>
<mrow>
<msup>
<mrow>
<mn>29.8</mn>
</mrow>
<mn>2</mn>
</msup>
</mrow>
<mo>+</mo>
<mrow>
<msup>
<mrow>
<mn>105.7</mn>
</mrow>
<mn>2</mn>
</msup>
</mrow>
</msqrt>
</math></span> + 29.8 =<strong>»</strong> 139.6 <strong>«</strong>MeV<strong>»</strong></p>
<p> </p>
<p><em>Final value to at least 3 sig figs required for mark.</em></p>
<p><strong><em>[2 marks]</em></strong></p>
<div class="question_part_label">a.ii.</div>
</div>
<div class="question" style="padding-left: 20px;">
<p>139.6 MeVc<sup>–2</sup></p>
<p> </p>
<p><em>Units required.</em></p>
<p><em>Accept 140 MeVc<sup>–</sup></em><sup><em>2</em></sup><em>.</em></p>
<p><strong><em>[1 mark]</em></strong></p>
<div class="question_part_label">b.</div>
</div>
<h2 style="margin-top: 1em">Examiners report</h2>
<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">a.i.</div>
</div>
<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">a.ii.</div>
</div>
<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">b.</div>
</div>
<br><hr><br>