Unit 6 Practical Quick Reference | Flowxiom<\/title>\n<meta name=\"description\" content=\"Unit 6 Practical Quick Reference \u2014 Edexcel A-level Physics WPH. \">\n<link rel=\"canonical\" href=\"https:\/\/flowxiom.com\/edexcel-physics-unit-6-practical-quick-reference\/\">\n\n\n<script>\nMathJax = {\n tex: { inlineMath: [['\\\\(','\\\\)']], displayMath: [['\\\\[','\\\\]']] },\n svg: { fontCache: 'global' }\n};\n<\/script>\n<script async src=\"https:\/\/cdn.jsdelivr.net\/npm\/mathjax@3\/es5\/tex-svg.js\"><\/script>\n\n<style>\n:root{--accent:#2563eb;--warn-bg:#fef9c3;--warn-border:#ca8a04;--formula-bg:#eff6ff;--formula-border:#2563eb;}\nbody{font-family:system-ui,sans-serif;max-width:860px;margin:0 auto;padding:1.5rem;line-height:1.7;color:#1e293b;}\nh1{font-size:2rem;border-bottom:3px solid var(--accent);padding-bottom:.4rem;}\nh2{font-size:1.4rem;color:var(--accent);margin-top:2rem;}\nh3{font-size:1.1rem;margin-top:1.4rem;}\ntable{border-collapse:collapse;width:100%;margin:1rem 0;}\nth,td{border:1px solid #cbd5e1;padding:.5rem .75rem;text-align:left;}\nth{background:#e2e8f0;}\npre,code{background:#f1f5f9;border-radius:4px;}\npre{padding:1rem;overflow-x:auto;}\ncode{padding:.1rem .3rem;font-size:.9em;}\n.seo-warning-box{background:var(--warn-bg);border-left:4px solid var(--warn-border);padding:.75rem 1rem;margin:1rem 0;border-radius:0 6px 6px 0;}\n.seo-note-box{background:#f0fdf4;border-left:4px solid #16a34a;padding:.75rem 1rem;margin:1rem 0;border-radius:0 6px 6px 0;}\nsection.formula-card{background:var(--formula-bg);border:1px solid var(--formula-border);border-radius:8px;padding:1rem 1.25rem;margin:1.5rem 0;}\ndetails{border:1px solid #e2e8f0;border-radius:6px;padding:.5rem 1rem;margin:.75rem 0;}\nsummary{cursor:pointer;font-weight:600;}\n.answer-block{margin-top:.5rem;padding-top:.5rem;border-top:1px solid #e2e8f0;overflow-x:auto;}\n.answer-block p{margin:.25rem 0;}\n.numbered-step{padding-left:1.5rem;position:relative;}\nhr{border:none;border-top:1px solid #e2e8f0;margin:2rem 0;}\n.toc{background:#f8fafc;border:1px solid #e2e8f0;border-radius:8px;padding:1rem 1.5rem;margin-bottom:2rem;}\n.toc h2{margin-top:0;font-size:1.1rem;}\n.toc ul{margin:0;padding-left:1.2rem;}\n.toc a{color:var(--accent);text-decoration:none;}\n.site-footer{margin-top:3rem;padding-top:1rem;border-top:2px solid var(--accent);font-size:.9rem;color:#64748b;}\n<\/style>\n<\/head>\n<body>\n<nav class=\"toc\"><h2>Contents<\/h2><ul>\n <li><a href=\"#6-core-practicals\">6 Core Practicals<\/a><\/li>\n <li><a href=\"#wph16-planning-questions\">WPH16 Planning Questions<\/a><\/li>\n <li><a href=\"#wph16-q2-data-analysis-guide\">WPH16 Q2: Data Analysis Guide<\/a><\/li>\n <li><a href=\"#note-on-error-bars-in-past-papers\">Note on Error Bars in Past Papers<\/a><\/li>\n<\/ul><\/nav>\n<h1>Unit 6 Practical Quick Reference<\/h1>\n<p><strong>Free resource by <a href=\"https:\/\/flowxiom.com\">Flowxiom<\/a> \u2014 Edexcel A-level Physics<\/strong><\/p>\n<p><em>Not everything. Just what’s on the paper. High-frequency topics only \u2014 covering ~80% of exam marks.<\/em><\/p>\n<p>Edexcel A-level Physics | A2 Core Practicals | WPH16<\/p>\n<p>Unit 6 builds on Unit 3 skills but demands more rigorous data processing and uncertainty analysis.<\/p>\n<p>See also: <strong>01 Uncertainty Quick Reference<\/strong> for graph and uncertainty format rules.<\/p>\n<hr>\n<h2 id=\"6-core-practicals\">6 Core Practicals<\/h2>\n<h3 id=\"practical-1-charging-and-discharging-capacitors\">Practical 1: Charging and Discharging Capacitors<\/h3>\n<p><strong>Aim:<\/strong> Determine time constant \\(RC\\) or capacitance \\(C\\)<\/p>\n<p><strong>Linearisation:<\/strong><\/p>\n<p>\\[\\ln V = -\\frac{1}{RC} \\cdot t + \\ln V_0\\]<\/p>\n<p>Plot \\(\\ln V\\) against \\(t\\):<\/p>\n<ul>\n<li>Gradient \\(= -1\/RC\\) (negative)<\/li>\n<li>y-intercept \\(= \\ln V_0\\)<\/li>\n<\/ul>\n<p><strong>Key operations:<\/strong><\/p>\n<ul>\n<li>Use a <strong>high-resistance voltmeter<\/strong> \u2014 prevents meter discharging capacitor<\/li>\n<li>If discharge is too fast: use a data logger with voltage sensor<\/li>\n<\/ul>\n<p><strong>Note:<\/strong> Axis label must be written as \\(\\ln(V\/\\text{V})\\)<\/p>\n<hr>\n<h3 id=\"practical-2-investigating-simple-harmonic-motion\">Practical 2: Investigating Simple Harmonic Motion<\/h3>\n<p><strong>Pendulum aim:<\/strong> Determine \\(g\\)<\/p>\n<p>\\[T^2 = \\frac{4\\pi^2}{g} \\cdot l\\]<\/p>\n<p>Plot \\(T^2\\) against \\(l\\); gradient \\(= 4\\pi^2\/g\\)<\/p>\n<p><strong>Spring-mass aim:<\/strong> Determine spring constant \\(k\\)<\/p>\n<p>\\[T^2 = \\frac{4\\pi^2}{k} \\cdot m\\]<\/p>\n<p>Plot \\(T^2\\) against \\(m\\); gradient \\(= 4\\pi^2\/k\\)<\/p>\n<p><strong>Key operations:<\/strong><\/p>\n<ul>\n<li>Time 20 complete oscillations; divide by 20 \u2014 reduces percentage uncertainty<\/li>\n<li>Set fiducial marker at equilibrium position \u2014 speed is maximum there, timing is most accurate<\/li>\n<li>Keep pendulum amplitude \\(< 10\u00b0\\) to satisfy small-angle approximation for SHM<\/li>\n<\/ul>\n<hr>\n<h3 id=\"practical-3-force-on-a-currentcarrying-conductor-in-a-magnetic-field\">Practical 3: Force on a Current-Carrying Conductor in a Magnetic Field<\/h3>\n<p><strong>Aim:<\/strong> Determine magnetic flux density \\(B\\) (\\(F = BIl\\))<\/p>\n<p><strong>Method:<\/strong><\/p>\n<p class=\"numbered-step\">Place magnet on electronic balance; tare to zero<\/p>\n<p class=\"numbered-step\">By Newton’s third law: force on wire = change in balance reading \u00d7 \\(g\\)<\/p>\n<p class=\"numbered-step\">Plot \\(F\\) against \\(I\\); gradient \\(= Bl\\)<\/p>\n<p><strong>Note:<\/strong> Switch off circuit immediately after each reading \u2014 prevents resistance change due to heating.<\/p>\n<hr>\n<h3 id=\"practical-4-investigating-gas-laws\">Practical 4: Investigating Gas Laws<\/h3>\n<p><strong>Verifying Boyle’s Law (\\(pV = \\text{constant}\\), constant temperature):<\/strong><\/p>\n<ul>\n<li>Vary the volume \\(V\\) of gas in a syringe; record pressure \\(p\\)<\/li>\n<li>Plot \\(p\\) against \\(1\/V\\) \u2014 should give a straight line through the origin<\/li>\n<\/ul>\n<p><strong>Key operations:<\/strong><\/p>\n<ul>\n<li>After compressing the gas, <strong>wait<\/strong> before taking readings \u2014 allow temperature to return to room temperature<\/li>\n<li>Compress slowly \u2014 rapid compression increases gas temperature<\/li>\n<\/ul>\n<p><strong>Measuring specific heat capacity:<\/strong><\/p>\n<p>\\[E = VIt = mc\\Delta\\theta\\]<\/p>\n<ul>\n<li>Source of error: heat loss to surroundings<\/li>\n<li>Improvement: add insulation, use a lid, stir thoroughly for uniform temperature<\/li>\n<\/ul>\n<hr>\n<h3 id=\"practical-5-thermal-properties-of-matter\">Practical 5: Thermal Properties of Matter<\/h3>\n<p><strong>Specific heat capacity:<\/strong><\/p>\n<ul>\n<li>Use electrical heater; record temperature vs time<\/li>\n<li>\\(c = \\dfrac{VIt}{m\\Delta\\theta}\\)<\/li>\n<\/ul>\n<p><strong>Specific latent heat:<\/strong><\/p>\n<ul>\n<li>Temperature is constant during change of state<\/li>\n<li>\\(L = \\dfrac{VIt}{m}\\)<\/li>\n<\/ul>\n<p><strong>Key precautions:<\/strong><\/p>\n<p><em>Specific Heat Capacity:<\/em><\/p>\n<ul>\n<li>Use lagging and lid to reduce heat loss to surroundings<\/li>\n<li>Add drops of oil in holes to ensure good thermal contact (for solid blocks)<\/li>\n<li>Wait after switching off until max temperature is reached (thermal equilibrium)<\/li>\n<\/ul>\n<p><em>Specific Latent Heat of Fusion:<\/em><\/p>\n<ul>\n<li>Use crushed ice for larger surface area and uniform heating<\/li>\n<li>Ensure ice is at 0\u00b0C so energy only goes to changing state<\/li>\n<li>Use an unheated control apparatus to correct for mass melted due to room temperature<\/li>\n<\/ul>\n<p><em>Specific Latent Heat of Vaporisation:<\/em><\/p>\n<ul>\n<li>Wait for steady boiling before starting timing<\/li>\n<li>Use lid to reduce convection heat loss, with a hole to prevent pressure build-up<\/li>\n<\/ul>\n<hr>\n<h3 id=\"practical-6-radioactivity-and-nuclear-decay\">Practical 6: Radioactivity and Nuclear Decay<\/h3>\n<p><strong>Aim:<\/strong> Determine half-life; verify the random nature of decay<\/p>\n<p><strong>Essential first step:<\/strong> Measure background radiation (average over 10 minutes)<\/p>\n<p>\\[\\text{corrected count rate} = \\text{measured count rate} – \\text{background count rate}\\]<\/p>\n<p><strong>Linearisation:<\/strong><\/p>\n<p>\\[\\ln A = -\\lambda t + \\ln A_0\\]<\/p>\n<p>Plot \\(\\ln A\\) against \\(t\\); gradient \\(= -\\lambda\\); half-life \\(= \\ln 2 \/ \\lambda\\)<\/p>\n<p><strong>Safety precautions (must state at least 3):<\/strong><\/p>\n<p class=\"numbered-step\">Use long-handled tongs \u2014 never handle source directly<\/p>\n<p class=\"numbered-step\">Return source to lead-lined container when not in use<\/p>\n<p class=\"numbered-step\">Never point source at any person<\/p>\n<p class=\"numbered-step\">Minimise time of exposure<\/p>\n<hr>\n<h2 id=\"wph16-planning-questions\">WPH16 Planning Questions<\/h2>\n<h3 id=\"typical-question-format\">Typical Question Format<\/h3>\n<div class=\"seo-note-box\">\n<p>“Design an experiment to verify the relationship between X and Y using a straight-line graph”<\/p>\n<\/div>\n<h3 id=\"key-points-to-cover\">Key Points to Cover<\/h3>\n<p class=\"numbered-step\"><strong>Variables<\/strong>: independent, dependent, control variables<\/p>\n<p class=\"numbered-step\"><strong>Linearisation<\/strong>: state which quantities to plot to give a straight line<\/p>\n<p class=\"numbered-step\"><strong>Gradient\/intercept<\/strong>: how to extract the target quantity from the graph<\/p>\n<p class=\"numbered-step\"><strong>Repeats<\/strong>: mention repeating measurements and averaging<\/p>\n<p class=\"numbered-step\"><strong>Error bars<\/strong>: how to draw error bars on the graph<\/p>\n<h3 id=\"common-linearisation-templates\">Common Linearisation Templates<\/h3>\n<table>\n<thead><tr><th>Relationship<\/th><th>Graph to plot<\/th><th>Gradient<\/th><\/tr><\/thead>\n<tr><td>\\(y = kx^2\\)<\/td><td>\\(y\\) vs \\(x^2\\)<\/td><td>\\(k\\)<\/td><\/tr>\n<tr><td>\\(y = ax^n\\)<\/td><td>\\(\\lg y\\) vs \\(\\lg x\\)<\/td><td>\\(n\\)<\/td><\/tr>\n<tr><td>\\(V = V_0 e^{-t\/RC}\\)<\/td><td>\\(\\ln V\\) vs \\(t\\)<\/td><td>\\(-1\/RC\\)<\/td><\/tr>\n<tr><td>\\(T^2 = (4\\pi^2\/g) \\cdot l\\)<\/td><td>\\(T^2\\) vs \\(l\\)<\/td><td>\\(4\\pi^2\/g\\)<\/td><\/tr>\n<tr><td>\\(A = A_0 e^{-\\lambda t}\\)<\/td><td>\\(\\ln A\\) vs \\(t\\)<\/td><td>\\(-\\lambda\\)<\/td><\/tr>\n<\/table>\n\n<hr>\n<h2 id=\"wph16-q2-data-analysis-guide\">WPH16 Q2: Data Analysis Guide<\/h2>\n<h3 id=\"typical-structure\">Typical Structure<\/h3>\n<p>WPH16 Q2 provides experimental data and asks you to:<\/p>\n<p class=\"numbered-step\">Complete the table (calculate derived quantities, logarithms, propagate uncertainties)<\/p>\n<p class=\"numbered-step\">Draw linearised graph with error bars<\/p>\n<p class=\"numbered-step\">Calculate target quantity from gradient\/intercept<\/p>\n<p class=\"numbered-step\">Write conclusion comparing with theoretical value<\/p>\n<h3 id=\"stepbystep-guide\">Step-by-Step Guide<\/h3>\n<p><strong>Step 1: Complete the table<\/strong><\/p>\n<ul>\n<li>Calculate derived quantities (e.g. \\(\\ln V\\), \\(T^2\\), \\(1\/V\\))<\/li>\n<li>\\(\\ln\\) values: 3 decimal places<\/li>\n<li>Uncertainty in \\(x^2\\): \\(\\dfrac{\\Delta(x^2)}{x^2} = 2\\dfrac{\\Delta x}{x}\\)<\/li>\n<\/ul>\n<p><strong>Step 2: Calculate error bars<\/strong><\/p>\n<p>\\[\\text{upper bar} = \\ln(V + \\Delta V) – \\ln V \\qquad \\text{lower bar} = \\ln V – \\ln(V – \\Delta V)\\]<\/p>\n<p>These are <strong>asymmetric<\/strong> \u2014 calculate each side separately.<\/p>\n<p><strong>Step 3: Draw the graph<\/strong><\/p>\n<ul>\n<li>Error bars on every point \u2014 compulsory<\/li>\n<li>Best-fit line must pass through all error bars<\/li>\n<li>Anomalous point: circle it; do not include in best-fit line; but still plot it<\/li>\n<\/ul>\n<p><strong>Step 4: Read gradient and intercept<\/strong><\/p>\n<ul>\n<li>Use two points on the <strong>line<\/strong> (not data points); use as large a triangle as possible<\/li>\n<li>Uncertainty in gradient: draw steepest and shallowest lines through all error bars, then:<\/li>\n<\/ul>\n<p>\\[\\Delta k = \\frac{k_{max} – k_{min}}{2}\\]<\/p>\n<p><strong>Step 5: Write conclusion<\/strong><\/p>\n<table>\n<thead><tr><th>Situation<\/th><th>Model conclusion<\/th><\/tr><\/thead>\n<tr><td>Straight line through origin<\/td><td>“The graph is a straight line through the origin, confirming X \u221d Y.”<\/td><\/tr>\n<tr><td>Straight line, not through origin<\/td><td>“X and Y are linearly related but not directly proportional.”<\/td><\/tr>\n<tr><td>Curved graph<\/td><td>“The graph is not linear, inconsistent with the proposed equation.”<\/td><\/tr>\n<\/table>\n\n<h3 id=\"handling-anomalous-points\">Handling Anomalous Points<\/h3>\n<ul>\n<li>Circle it on the graph<\/li>\n<li>State it is excluded from the best-fit line<\/li>\n<li>Do <strong>NOT<\/strong> omit it \u2014 it must still be plotted<\/li>\n<\/ul>\n<hr>\n<h2 id=\"note-on-error-bars-in-past-papers\">Note on Error Bars in Past Papers<\/h2>\n<p>Although full error bar graphs are rarely drawn in timed exams, the underlying concepts are examined in these ways:<\/p>\n<p class=\"numbered-step\"><strong>Calculation focus<\/strong>: Questions typically ask for percentage uncertainty or gradient uncertainty directly.<\/p>\n<p class=\"numbered-step\"><strong>Key concepts to master:<\/strong><\/p>\n<p>– Error bars represent the absolute uncertainty of each data point<\/p>\n<p>– Anomalous point: the best-fit line does not pass through its error bars<\/p>\n<p>– Gradient uncertainty: \\(\\text{uncertainty} = \\text{best gradient} – \\text{worst acceptable gradient}\\)<\/p>\n<p>– To find maximum possible value of a quantity: <em>“Draw a worst acceptable line through the error bars.”<\/em><\/p>\n<hr>\n<p><em>Want more? Visit <a href=\"https:\/\/flowxiom.com\">flowxiom.com<\/a><\/em><\/p>\n<footer class=\"site-footer\">\n <p>Free resource by <a href=\"https:\/\/flowxiom.com\">Flowxiom<\/a> \u2014 Edexcel A-level Physics<br>\n High-frequency topics only, covering ~80% of exam marks.<\/p>\n<\/footer>\n<\/body>\n<\/html>\n\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>This comprehensive guide provides a high-yield reference for the Edexcel A-level Physics Unit 6 (WPH16) practical exam. It details the core A2 experiments, including the investigation of capacitor discharge, magnetic field strength, and the half-life of radioactive sources. The resource emphasizes advanced data analysis techniques such as logarithmic linearization and the calculation of uncertainties in gradients and intercepts. With a focus on experimental evaluation and the “Sentence Bank” for common improvements, this guide is an essential tool for students aiming to master the practical skills required for their final physics papers.<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-50","post","type-post","status-publish","format-standard","hentry","category-exam-sprint-pack-physics-exam-sprint-pack"],"_links":{"self":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts\/50","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/comments?post=50"}],"version-history":[{"count":2,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts\/50\/revisions"}],"predecessor-version":[{"id":52,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts\/50\/revisions\/52"}],"wp:attachment":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/media?parent=50"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/categories?post=50"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/tags?post=50"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":50,"date":"2026-04-17T16:28:22","date_gmt":"2026-04-17T16:28:22","guid":{"rendered":"https:\/\/flowxiom.com\/?p=50"},"modified":"2026-04-17T16:29:36","modified_gmt":"2026-04-17T16:29:36","slug":"unit-6-practical-quick-reference","status":"publish","type":"post","link":"https:\/\/flowxiom.com\/index.php\/2026\/04\/17\/unit-6-practical-quick-reference\/","title":{"rendered":"Unit 6 Practical Quick Reference"},"content":{"rendered":"\n\n\n\n\n\nUnit 6 Practical Quick Reference | Flowxiom<\/title>\n<meta name=\"description\" content=\"Unit 6 Practical Quick Reference \u2014 Edexcel A-level Physics WPH. \">\n<link rel=\"canonical\" href=\"https:\/\/flowxiom.com\/edexcel-physics-unit-6-practical-quick-reference\/\">\n\n\n<script>\nMathJax = {\n tex: { inlineMath: [['\\\\(','\\\\)']], displayMath: [['\\\\[','\\\\]']] },\n svg: { fontCache: 'global' }\n};\n<\/script>\n<script async src=\"https:\/\/cdn.jsdelivr.net\/npm\/mathjax@3\/es5\/tex-svg.js\"><\/script>\n\n<style>\n:root{--accent:#2563eb;--warn-bg:#fef9c3;--warn-border:#ca8a04;--formula-bg:#eff6ff;--formula-border:#2563eb;}\nbody{font-family:system-ui,sans-serif;max-width:860px;margin:0 auto;padding:1.5rem;line-height:1.7;color:#1e293b;}\nh1{font-size:2rem;border-bottom:3px solid var(--accent);padding-bottom:.4rem;}\nh2{font-size:1.4rem;color:var(--accent);margin-top:2rem;}\nh3{font-size:1.1rem;margin-top:1.4rem;}\ntable{border-collapse:collapse;width:100%;margin:1rem 0;}\nth,td{border:1px solid #cbd5e1;padding:.5rem .75rem;text-align:left;}\nth{background:#e2e8f0;}\npre,code{background:#f1f5f9;border-radius:4px;}\npre{padding:1rem;overflow-x:auto;}\ncode{padding:.1rem .3rem;font-size:.9em;}\n.seo-warning-box{background:var(--warn-bg);border-left:4px solid var(--warn-border);padding:.75rem 1rem;margin:1rem 0;border-radius:0 6px 6px 0;}\n.seo-note-box{background:#f0fdf4;border-left:4px solid #16a34a;padding:.75rem 1rem;margin:1rem 0;border-radius:0 6px 6px 0;}\nsection.formula-card{background:var(--formula-bg);border:1px solid var(--formula-border);border-radius:8px;padding:1rem 1.25rem;margin:1.5rem 0;}\ndetails{border:1px solid #e2e8f0;border-radius:6px;padding:.5rem 1rem;margin:.75rem 0;}\nsummary{cursor:pointer;font-weight:600;}\n.answer-block{margin-top:.5rem;padding-top:.5rem;border-top:1px solid #e2e8f0;overflow-x:auto;}\n.answer-block p{margin:.25rem 0;}\n.numbered-step{padding-left:1.5rem;position:relative;}\nhr{border:none;border-top:1px solid #e2e8f0;margin:2rem 0;}\n.toc{background:#f8fafc;border:1px solid #e2e8f0;border-radius:8px;padding:1rem 1.5rem;margin-bottom:2rem;}\n.toc h2{margin-top:0;font-size:1.1rem;}\n.toc ul{margin:0;padding-left:1.2rem;}\n.toc a{color:var(--accent);text-decoration:none;}\n.site-footer{margin-top:3rem;padding-top:1rem;border-top:2px solid var(--accent);font-size:.9rem;color:#64748b;}\n<\/style>\n<\/head>\n<body>\n<nav class=\"toc\"><h2>Contents<\/h2><ul>\n <li><a href=\"#6-core-practicals\">6 Core Practicals<\/a><\/li>\n <li><a href=\"#wph16-planning-questions\">WPH16 Planning Questions<\/a><\/li>\n <li><a href=\"#wph16-q2-data-analysis-guide\">WPH16 Q2: Data Analysis Guide<\/a><\/li>\n <li><a href=\"#note-on-error-bars-in-past-papers\">Note on Error Bars in Past Papers<\/a><\/li>\n<\/ul><\/nav>\n<h1>Unit 6 Practical Quick Reference<\/h1>\n<p><strong>Free resource by <a href=\"https:\/\/flowxiom.com\">Flowxiom<\/a> \u2014 Edexcel A-level Physics<\/strong><\/p>\n<p><em>Not everything. Just what’s on the paper. High-frequency topics only \u2014 covering ~80% of exam marks.<\/em><\/p>\n<p>Edexcel A-level Physics | A2 Core Practicals | WPH16<\/p>\n<p>Unit 6 builds on Unit 3 skills but demands more rigorous data processing and uncertainty analysis.<\/p>\n<p>See also: <strong>01 Uncertainty Quick Reference<\/strong> for graph and uncertainty format rules.<\/p>\n<hr>\n<h2 id=\"6-core-practicals\">6 Core Practicals<\/h2>\n<h3 id=\"practical-1-charging-and-discharging-capacitors\">Practical 1: Charging and Discharging Capacitors<\/h3>\n<p><strong>Aim:<\/strong> Determine time constant \\(RC\\) or capacitance \\(C\\)<\/p>\n<p><strong>Linearisation:<\/strong><\/p>\n<p>\\[\\ln V = -\\frac{1}{RC} \\cdot t + \\ln V_0\\]<\/p>\n<p>Plot \\(\\ln V\\) against \\(t\\):<\/p>\n<ul>\n<li>Gradient \\(= -1\/RC\\) (negative)<\/li>\n<li>y-intercept \\(= \\ln V_0\\)<\/li>\n<\/ul>\n<p><strong>Key operations:<\/strong><\/p>\n<ul>\n<li>Use a <strong>high-resistance voltmeter<\/strong> \u2014 prevents meter discharging capacitor<\/li>\n<li>If discharge is too fast: use a data logger with voltage sensor<\/li>\n<\/ul>\n<p><strong>Note:<\/strong> Axis label must be written as \\(\\ln(V\/\\text{V})\\)<\/p>\n<hr>\n<h3 id=\"practical-2-investigating-simple-harmonic-motion\">Practical 2: Investigating Simple Harmonic Motion<\/h3>\n<p><strong>Pendulum aim:<\/strong> Determine \\(g\\)<\/p>\n<p>\\[T^2 = \\frac{4\\pi^2}{g} \\cdot l\\]<\/p>\n<p>Plot \\(T^2\\) against \\(l\\); gradient \\(= 4\\pi^2\/g\\)<\/p>\n<p><strong>Spring-mass aim:<\/strong> Determine spring constant \\(k\\)<\/p>\n<p>\\[T^2 = \\frac{4\\pi^2}{k} \\cdot m\\]<\/p>\n<p>Plot \\(T^2\\) against \\(m\\); gradient \\(= 4\\pi^2\/k\\)<\/p>\n<p><strong>Key operations:<\/strong><\/p>\n<ul>\n<li>Time 20 complete oscillations; divide by 20 \u2014 reduces percentage uncertainty<\/li>\n<li>Set fiducial marker at equilibrium position \u2014 speed is maximum there, timing is most accurate<\/li>\n<li>Keep pendulum amplitude \\(< 10\u00b0\\) to satisfy small-angle approximation for SHM<\/li>\n<\/ul>\n<hr>\n<h3 id=\"practical-3-force-on-a-currentcarrying-conductor-in-a-magnetic-field\">Practical 3: Force on a Current-Carrying Conductor in a Magnetic Field<\/h3>\n<p><strong>Aim:<\/strong> Determine magnetic flux density \\(B\\) (\\(F = BIl\\))<\/p>\n<p><strong>Method:<\/strong><\/p>\n<p class=\"numbered-step\">Place magnet on electronic balance; tare to zero<\/p>\n<p class=\"numbered-step\">By Newton’s third law: force on wire = change in balance reading \u00d7 \\(g\\)<\/p>\n<p class=\"numbered-step\">Plot \\(F\\) against \\(I\\); gradient \\(= Bl\\)<\/p>\n<p><strong>Note:<\/strong> Switch off circuit immediately after each reading \u2014 prevents resistance change due to heating.<\/p>\n<hr>\n<h3 id=\"practical-4-investigating-gas-laws\">Practical 4: Investigating Gas Laws<\/h3>\n<p><strong>Verifying Boyle’s Law (\\(pV = \\text{constant}\\), constant temperature):<\/strong><\/p>\n<ul>\n<li>Vary the volume \\(V\\) of gas in a syringe; record pressure \\(p\\)<\/li>\n<li>Plot \\(p\\) against \\(1\/V\\) \u2014 should give a straight line through the origin<\/li>\n<\/ul>\n<p><strong>Key operations:<\/strong><\/p>\n<ul>\n<li>After compressing the gas, <strong>wait<\/strong> before taking readings \u2014 allow temperature to return to room temperature<\/li>\n<li>Compress slowly \u2014 rapid compression increases gas temperature<\/li>\n<\/ul>\n<p><strong>Measuring specific heat capacity:<\/strong><\/p>\n<p>\\[E = VIt = mc\\Delta\\theta\\]<\/p>\n<ul>\n<li>Source of error: heat loss to surroundings<\/li>\n<li>Improvement: add insulation, use a lid, stir thoroughly for uniform temperature<\/li>\n<\/ul>\n<hr>\n<h3 id=\"practical-5-thermal-properties-of-matter\">Practical 5: Thermal Properties of Matter<\/h3>\n<p><strong>Specific heat capacity:<\/strong><\/p>\n<ul>\n<li>Use electrical heater; record temperature vs time<\/li>\n<li>\\(c = \\dfrac{VIt}{m\\Delta\\theta}\\)<\/li>\n<\/ul>\n<p><strong>Specific latent heat:<\/strong><\/p>\n<ul>\n<li>Temperature is constant during change of state<\/li>\n<li>\\(L = \\dfrac{VIt}{m}\\)<\/li>\n<\/ul>\n<p><strong>Key precautions:<\/strong><\/p>\n<p><em>Specific Heat Capacity:<\/em><\/p>\n<ul>\n<li>Use lagging and lid to reduce heat loss to surroundings<\/li>\n<li>Add drops of oil in holes to ensure good thermal contact (for solid blocks)<\/li>\n<li>Wait after switching off until max temperature is reached (thermal equilibrium)<\/li>\n<\/ul>\n<p><em>Specific Latent Heat of Fusion:<\/em><\/p>\n<ul>\n<li>Use crushed ice for larger surface area and uniform heating<\/li>\n<li>Ensure ice is at 0\u00b0C so energy only goes to changing state<\/li>\n<li>Use an unheated control apparatus to correct for mass melted due to room temperature<\/li>\n<\/ul>\n<p><em>Specific Latent Heat of Vaporisation:<\/em><\/p>\n<ul>\n<li>Wait for steady boiling before starting timing<\/li>\n<li>Use lid to reduce convection heat loss, with a hole to prevent pressure build-up<\/li>\n<\/ul>\n<hr>\n<h3 id=\"practical-6-radioactivity-and-nuclear-decay\">Practical 6: Radioactivity and Nuclear Decay<\/h3>\n<p><strong>Aim:<\/strong> Determine half-life; verify the random nature of decay<\/p>\n<p><strong>Essential first step:<\/strong> Measure background radiation (average over 10 minutes)<\/p>\n<p>\\[\\text{corrected count rate} = \\text{measured count rate} – \\text{background count rate}\\]<\/p>\n<p><strong>Linearisation:<\/strong><\/p>\n<p>\\[\\ln A = -\\lambda t + \\ln A_0\\]<\/p>\n<p>Plot \\(\\ln A\\) against \\(t\\); gradient \\(= -\\lambda\\); half-life \\(= \\ln 2 \/ \\lambda\\)<\/p>\n<p><strong>Safety precautions (must state at least 3):<\/strong><\/p>\n<p class=\"numbered-step\">Use long-handled tongs \u2014 never handle source directly<\/p>\n<p class=\"numbered-step\">Return source to lead-lined container when not in use<\/p>\n<p class=\"numbered-step\">Never point source at any person<\/p>\n<p class=\"numbered-step\">Minimise time of exposure<\/p>\n<hr>\n<h2 id=\"wph16-planning-questions\">WPH16 Planning Questions<\/h2>\n<h3 id=\"typical-question-format\">Typical Question Format<\/h3>\n<div class=\"seo-note-box\">\n<p>“Design an experiment to verify the relationship between X and Y using a straight-line graph”<\/p>\n<\/div>\n<h3 id=\"key-points-to-cover\">Key Points to Cover<\/h3>\n<p class=\"numbered-step\"><strong>Variables<\/strong>: independent, dependent, control variables<\/p>\n<p class=\"numbered-step\"><strong>Linearisation<\/strong>: state which quantities to plot to give a straight line<\/p>\n<p class=\"numbered-step\"><strong>Gradient\/intercept<\/strong>: how to extract the target quantity from the graph<\/p>\n<p class=\"numbered-step\"><strong>Repeats<\/strong>: mention repeating measurements and averaging<\/p>\n<p class=\"numbered-step\"><strong>Error bars<\/strong>: how to draw error bars on the graph<\/p>\n<h3 id=\"common-linearisation-templates\">Common Linearisation Templates<\/h3>\n<table>\n<thead><tr><th>Relationship<\/th><th>Graph to plot<\/th><th>Gradient<\/th><\/tr><\/thead>\n<tr><td>\\(y = kx^2\\)<\/td><td>\\(y\\) vs \\(x^2\\)<\/td><td>\\(k\\)<\/td><\/tr>\n<tr><td>\\(y = ax^n\\)<\/td><td>\\(\\lg y\\) vs \\(\\lg x\\)<\/td><td>\\(n\\)<\/td><\/tr>\n<tr><td>\\(V = V_0 e^{-t\/RC}\\)<\/td><td>\\(\\ln V\\) vs \\(t\\)<\/td><td>\\(-1\/RC\\)<\/td><\/tr>\n<tr><td>\\(T^2 = (4\\pi^2\/g) \\cdot l\\)<\/td><td>\\(T^2\\) vs \\(l\\)<\/td><td>\\(4\\pi^2\/g\\)<\/td><\/tr>\n<tr><td>\\(A = A_0 e^{-\\lambda t}\\)<\/td><td>\\(\\ln A\\) vs \\(t\\)<\/td><td>\\(-\\lambda\\)<\/td><\/tr>\n<\/table>\n\n<hr>\n<h2 id=\"wph16-q2-data-analysis-guide\">WPH16 Q2: Data Analysis Guide<\/h2>\n<h3 id=\"typical-structure\">Typical Structure<\/h3>\n<p>WPH16 Q2 provides experimental data and asks you to:<\/p>\n<p class=\"numbered-step\">Complete the table (calculate derived quantities, logarithms, propagate uncertainties)<\/p>\n<p class=\"numbered-step\">Draw linearised graph with error bars<\/p>\n<p class=\"numbered-step\">Calculate target quantity from gradient\/intercept<\/p>\n<p class=\"numbered-step\">Write conclusion comparing with theoretical value<\/p>\n<h3 id=\"stepbystep-guide\">Step-by-Step Guide<\/h3>\n<p><strong>Step 1: Complete the table<\/strong><\/p>\n<ul>\n<li>Calculate derived quantities (e.g. \\(\\ln V\\), \\(T^2\\), \\(1\/V\\))<\/li>\n<li>\\(\\ln\\) values: 3 decimal places<\/li>\n<li>Uncertainty in \\(x^2\\): \\(\\dfrac{\\Delta(x^2)}{x^2} = 2\\dfrac{\\Delta x}{x}\\)<\/li>\n<\/ul>\n<p><strong>Step 2: Calculate error bars<\/strong><\/p>\n<p>\\[\\text{upper bar} = \\ln(V + \\Delta V) – \\ln V \\qquad \\text{lower bar} = \\ln V – \\ln(V – \\Delta V)\\]<\/p>\n<p>These are <strong>asymmetric<\/strong> \u2014 calculate each side separately.<\/p>\n<p><strong>Step 3: Draw the graph<\/strong><\/p>\n<ul>\n<li>Error bars on every point \u2014 compulsory<\/li>\n<li>Best-fit line must pass through all error bars<\/li>\n<li>Anomalous point: circle it; do not include in best-fit line; but still plot it<\/li>\n<\/ul>\n<p><strong>Step 4: Read gradient and intercept<\/strong><\/p>\n<ul>\n<li>Use two points on the <strong>line<\/strong> (not data points); use as large a triangle as possible<\/li>\n<li>Uncertainty in gradient: draw steepest and shallowest lines through all error bars, then:<\/li>\n<\/ul>\n<p>\\[\\Delta k = \\frac{k_{max} – k_{min}}{2}\\]<\/p>\n<p><strong>Step 5: Write conclusion<\/strong><\/p>\n<table>\n<thead><tr><th>Situation<\/th><th>Model conclusion<\/th><\/tr><\/thead>\n<tr><td>Straight line through origin<\/td><td>“The graph is a straight line through the origin, confirming X \u221d Y.”<\/td><\/tr>\n<tr><td>Straight line, not through origin<\/td><td>“X and Y are linearly related but not directly proportional.”<\/td><\/tr>\n<tr><td>Curved graph<\/td><td>“The graph is not linear, inconsistent with the proposed equation.”<\/td><\/tr>\n<\/table>\n\n<h3 id=\"handling-anomalous-points\">Handling Anomalous Points<\/h3>\n<ul>\n<li>Circle it on the graph<\/li>\n<li>State it is excluded from the best-fit line<\/li>\n<li>Do <strong>NOT<\/strong> omit it \u2014 it must still be plotted<\/li>\n<\/ul>\n<hr>\n<h2 id=\"note-on-error-bars-in-past-papers\">Note on Error Bars in Past Papers<\/h2>\n<p>Although full error bar graphs are rarely drawn in timed exams, the underlying concepts are examined in these ways:<\/p>\n<p class=\"numbered-step\"><strong>Calculation focus<\/strong>: Questions typically ask for percentage uncertainty or gradient uncertainty directly.<\/p>\n<p class=\"numbered-step\"><strong>Key concepts to master:<\/strong><\/p>\n<p>– Error bars represent the absolute uncertainty of each data point<\/p>\n<p>– Anomalous point: the best-fit line does not pass through its error bars<\/p>\n<p>– Gradient uncertainty: \\(\\text{uncertainty} = \\text{best gradient} – \\text{worst acceptable gradient}\\)<\/p>\n<p>– To find maximum possible value of a quantity: <em>“Draw a worst acceptable line through the error bars.”<\/em><\/p>\n<hr>\n<p><em>Want more? Visit <a href=\"https:\/\/flowxiom.com\">flowxiom.com<\/a><\/em><\/p>\n<footer class=\"site-footer\">\n <p>Free resource by <a href=\"https:\/\/flowxiom.com\">Flowxiom<\/a> \u2014 Edexcel A-level Physics<br>\n High-frequency topics only, covering ~80% of exam marks.<\/p>\n<\/footer>\n<\/body>\n<\/html>\n\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>This comprehensive guide provides a high-yield reference for the Edexcel A-level Physics Unit 6 (WPH16) practical exam. It details the core A2 experiments, including the investigation of capacitor discharge, magnetic field strength, and the half-life of radioactive sources. The resource emphasizes advanced data analysis techniques such as logarithmic linearization and the calculation of uncertainties in gradients and intercepts. With a focus on experimental evaluation and the “Sentence Bank” for common improvements, this guide is an essential tool for students aiming to master the practical skills required for their final physics papers.<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-50","post","type-post","status-publish","format-standard","hentry","category-exam-sprint-pack-physics-exam-sprint-pack"],"_links":{"self":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts\/50","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/comments?post=50"}],"version-history":[{"count":2,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts\/50\/revisions"}],"predecessor-version":[{"id":52,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/posts\/50\/revisions\/52"}],"wp:attachment":[{"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/media?parent=50"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/categories?post=50"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/flowxiom.com\/index.php\/wp-json\/wp\/v2\/tags?post=50"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}