hij Teacher Resource Bank GCE Physics B (Physics in Context) Other Guidance: • PHYB2 – Physics Keeps us Going Copyright © 2008 AQA and its licensors. All rights reserved. The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723) and a registered charity (registered charity number 1073334). Registered address: AQA, Devas Street, Manchester M15 6EX. Dr Michael Cresswell, Director General. Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 This document shows how the content for this unit could be taught. It indicates how topics can be clustered together with an approximate teaching duration (in weeks). Details of some possible actives to support teaching and learning are provided in the right hand column. Teachers will need to select appropriate activities for their teaching approaches and facilities available in the centre as there are far more activities quoted than can possibly be completed in the time available. If you have additional activities that you would like to share with teaching colleagues please contact the subject team who will update this document periodically. klm Copyright © 2008 AQA and its licensors. All rights reserved. 1 2 C(2) A/B(1) Use of a spring balance (or calibrated )spring to measure force on object on inclined plane Resolution of vectors into two components at right angles to each other Copyright © 2008 AQA and its licensors. All rights reserved. klm Analysis of motion of falling object (ticker tape or more sophisticated apparatus) Context: Describing motion Examples from Swimming and Track athletics; Driving; stopping and starting distances. Force board or two Newton meters balancing a loaded hanger showing the equilibrium of 3 forces at a point Longman advanced practical guide B.5 http://www.walter-fendt.de/ph14e/equilibrium.htm Advanced Physics Lab animation - Forces http://www.walter-fendt.de/ph14e/forceresol.htm http://www.walter-fendt.de/ph14e/inclplane.htm or Modellus (IOP) Context: Balanced forces on a rock climber http://www.walter-fendt.de/ph14e/resultant.htm Addition of two vectors by scale drawing and calculation Calculation limited to two vectors at right angles Examples should relate to force and velocity vectors in particular The forces perpendicular and at right angles to a body on an inclined plane due to its weight. Context: Direction - Examples from sporting activities, such as sailing, rowing and running angles to enable interception, and transport examples such as flight paths. Vectors and scalars – Examples to include speed, velocity, mass and force/weight MODULE 1 Moving People, People Moving This module considers how knowledge and understanding of forces underpins everyday activities such as transport, where reliability is important, and activities such as record breaking in sport. Weeks Specification Context and activities Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 klm D(1) http://www.walter-fendt.de/ph14e/projectile.htm 3 http://www.practicalphysics.org/go/Collection_59.html?topic_id=3&collecti on_id=59 http://www.practicalphysics.org/go/Collection_51.html?topic_id=3&collecti on_id=51 Accelerated motion expts with trolleys/gliders e.g linear air track glider attached to falling body. Data capture using digital cameras and camcorders Monkey and Hunter experiment Pulsed water droplets with stroboscope Range of projectile – marble into sand pit (IOP) Advanced Physics Lab animation – Shoot Use of fan carts Context; What makes motion change Examples from diving; skiing/ski jumping and throwing/ball sports Copyright © 2008 AQA and its licensors. All rights reserved. Appreciation that a body is in equilibrium when at rest or when moving with constant velocity Use of scale drawing or resolved forces to solve problems Conditions for equilibrium of two or three forces Advanced Physics Lab animation – Skater Advanced Physics Lab animation - Newton’s http://www.practicalphysics.org/go/Collection_49.html?topic_id=3&collecti on_id=49 Trolley experiments with motion sensors/light gates and timers opportunity to us datalogger Opportunity to analyse the motion of projectiles, vehicles and people using camera images Multimedia motion cd rom. Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 4 E(1) D(2) klm Context; Vehicles towing; Running shoes Temperature rise produced by falling objects *lead shot in tube’ Rubber band energy stored transferred to glider on air track for different extensions of band Nuffield metal staple fired vertically with rubber band (estimate height reaches) – health and safety issues Work done against friction by dragging a slider along a bench or inclined runway. Context; Looking at energy changes Examples from archery or throwing sports; bungee jumping; jumping and weight lifting. Impact craters (IOP) Investigating bounce height of balls –Trolley on ramp to compare gravitational potential energy with kinetic energy. Record flight of different types of ball using digital camera/control variables Projectile flight in controlled lab experiment(use compression spring in trolleys to fix initial speed or use rubber bands). Copyright © 2008 AQA and its licensors. All rights reserved. Elastic potential energy; Energy stored = area under force-extension graph 1 Energy stored = FΔL when F ∝ L 2 Work done = force x distance moved in the direction of the force = energy transferred W = Fs cosθ Work, energy and power Qualitative and quantitative application of energy conservation in a uniform gravitational field 1 ΔE p = mgΔh and ΔE k = mv 2 2 Use of equations of motion for movement at constant velocity 1 2 2 ⎛u +v⎞ and acceleration; v = u + at; s = ⎜ ⎟ t ; s = ut + at ; v = 2 ⎝ 2 ⎠ u2 + 2as http://www.practicalphysics.org/go/Collection_81.html?topic_id=3&collecti on_id=81 NASA info and video (from NASA) Video clip on parachutes Multimedia motion of space shuttle ball bearing falling through engine oil in large measuring cylinder Water rockets (kit) Weight falling through water connected to trolley/glider Pasco propeller trolley on inclined plane or with angled barrier Modellus (IOP) or other applets Understanding of rates of change with respect to time Δs Δv and a = v= Δt Δt Significance and calculation of gradient and area under s-t and v-t graphs for uniform and non-uniform motion Context; What if acceleration changes? Rocket take off; Skydiver; Parachutes Gliders, planes, parascending; Vehicles going faster Shapes of s-t, v-t and a-t graphs for uniformly accelerated motion Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 klm Copyright © 2008 AQA and its licensors. All rights reserved. For experiments go to http://www.practicalphysics.org/ : details of equipment and objectives Lots of other useful java applets on the web e.g. the collection on http://www.lon-capa.org/~mmp/applist/applets.htm Advanced Physics Practical Guide – Longman 0582 273226 9 Physics Through investigation – Gren Ireson Hodder and Stoughton 0 340 72040 9 5 http://www.practicalphysics.org/go/Collection_69.html?topic_id=39&collec tion_id=69 Case study: Safety features in road vehicles Power of student when e.g. running upstairs lifting a (1 – 2 kg) mass through a given height over a set time Press ups or pull ups if energetic! Advanced Physics Lab animation –work Advanced Physics Lab animations- John Murray http://www.physicslab.co.uk - The program is free to use. Energy conservation between energy source kinetic energy and gravitational potential energy, elastic potential energy, energy to deform and internal energy of surroundings. Explanation of the reduced force when momentum is dissipated over a longer time or energy over a longer distance Power = rate of doing work = rate of energy transfer ΔW P= = Fv Δt Stiffness k=F/ ΔL Transfer to kinetic energy or gravitational potential energy Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 6 Weeks A(½) klm Worksheet on steam engine Sankey + questions of Sankey for human body http://www.iop.org/Our_Activities/Schools_and_Colleges/Teaching_Res ources/Teaching%20Advanced%20Physics/Energy/Thermal%20physics /file_5203.doc Questions and good teaching notes / student materials from Unit G of RevNuff Free software for drawing the diagrams from an Excel spreadsheet http://www.doka.ch/sankey1.htm Copyright © 2008 AQA and its licensors. All rights reserved. Use and interpretation of Sankey diagrams representing energy changes Demo of energy conversion: steam engine; solar cell; heat toy http://scitoys.com/scitoys/scitoys/thermo/thermo.html Many data sources of data on energy usage linked to: http://www.open.ac.uk/T206/index.html Knowledge of the energy used at an individual, national and international level Carbon footprint: discussion and personal estimates: http://www.bp.com/extendedsectiongenericarticle.do?categoryId=90082 04&contentId=7015209&BPLinkTrace=1604280000 http://www.carbonfootprint.com/calculator.html discussion http://www.carbonfootprint.com/warming.html Book resource: Energy: University of Bath 16-19 project (data needs updating) Context and activities Context: Where does our energy come from and where does it go? This section should be taught in the context of solar, carbon-based and nuclear resources. Work is made quantitative through the use of the Sankey diagram. Up-to-date data for use in this section can be readily obtained from the Internet. Knowledge of the relative amounts of energy currently generated by different sources (UK only) Appreciation that solar energy may be used directly or from secondary sources such as wind and tides. Knowledge of the relative amounts of energy available from non renewable sources at a national and international level Specification MODULE 2 Energy and the Environment This module is about the sources of energy, how we utilise the energy and the consequences of increasing energy demand. The unit focuses on the value of electrical energy as a particularly convenient form. Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 klm B(1) Density ρ = Density, ice / water experiments Knowledge that a floating mass displaces its own mass of liquid Expt : investigate output of various processes using CO2 sensor with datalogger Copyright © 2008 AQA and its licensors. All rights reserved. m , V Principal of floatation/ Archimedes’ principle (calculations required) Rising tide level due to melting ice caps. Appreciation that melting of ice on land increases sea level but melting icebergs do not. Use of graphs of P/Wm2 against T/Kto compare power losses. Wiens law λmax T = constant Balance of emission/absorption – comparison with other planets Effects on environment http://www.environment-agency.gov.uk/?lang=_e Knowledge of the need for balance between energy inflow from the Sun and energy re-radiation from the Earth (links to next Section) Recognition that ‘global warming’ implies a lack of balance and that equilibrium may return at a higher temperature understanding that wavelengths are converted into the near infrared in the atmosphere New Scientist magazine contains many references to, and much data for, global temperature changes (esp. 30/08/06 issue) This is an ideal topic for internet research by students followed by poster / power point session or formal presentation Context: Impact of energy conversion? This section is taught in the context of the on-going debate that centres around global warming and its effects. There is much scope here for teaching issues in the context of How Science works. Understanding of the ‘greenhouse’ effect and that this is affected by CO2 levels in the atmosphere Knowledge of the major regions of the electromagnetic spectrum and their approximate wavelength and frequency values and where appropriate an appreciation of their possible effects on humans Factors that affect the rate at which the temperature of the Earth rises: Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 7 8 C(1) P A 4πr 2 P (links to Unit Energy conversion using solar cells Underwater turbine designs http://www.johnarmstrong1.pwp.blueyonder.co.uk/Turbines.htm Designs of turbines – output vs wind speed Expts/demonstrations with various turbine blade designs http://www.bwea.com/ Danish wind power site worth a look http://www.windpower.org/en/tour/wres/pow/index.htm Tidal: http://www.tidalelectric.com/History.htm includes some simple algebra of barrage Opportunity to introduce log-log graphs and graphical treatments in general Solar cell/panel efficiency expts klm Lamp experiment for inverse square law (small filament lamp / tube / LDR mounted on ruler) Good elementary outline of sources in Avison: The World of Physics also simple introduction at http://home.clara.net/darvill/altenerg/index.htm Excellent opportunities for research, critical appraisal and presentation opportunity by students. Context: Sources of renewable energy This section is taught in the context of the wide range of renewable energy sources. Throughout this section there is the need to consider How Science Works in that some of the Internet sources are written by (possibly prejudiced) pressure groups. Lot of information at the renewable energy centre http://www.therenewableenergycentre.co.uk/solar-heating/ Copyright © 2008 AQA and its licensors. All rights reserved. Estimation of energy conversation in a wave 1 Power available from wind = πr 2 ρv 3 2 PE ↔KE conversions and power considered in relation to tidal barrages, hydroelectric and pumped storage systems Role of sun in producing power from wind and tides Estimation of energy in a wave (links to Unit 2 wave ideas) 2) Inverse square law for a point source I = Intensity of power from the Sun I = Knowledge of at least one advantage and one disadvantage for each of the following sources; solar power, wind- wave conversions, tides, HEP, pumped storage, and wind turbine conversions. Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 klm C(3) Selection of [AP; ch 4] : Experiment 'Measuring resistance of good conductors' Rates of heating of different resistance wires – Use potato (as AP) or fruit batteries (kiwi fruit best) – 2p and 5p coins (Cu and Zn) – large internal resistance (∼kΩ) [AP; ch 2] Experiment 'Internal resistance of a source of emf' Context: Energy lost in transmission of electrical energy Components in a box type experiments Selection of some of the experiments outlined in AP [chap 2]: Demonstration 'Current and charge in electron beams' Demonstration 'Spooning charge' Demonstration 'Shuttling ball and ions in a flame' Demonstration 'Conduction by 'coloured' ions' Experiment 'Conduction by students' Context: Using the energy This section is taught in the context of the end use of electrical energy; motors / heaters / electrical storage cells should be discussed as converters of electrical energy to heat energy Copyright © 2008 AQA and its licensors. All rights reserved. Electromotive force and internal resistance and their measurement E ε= Q ε = IR + Ir ρL 1 Resistivity and electrical conductivity R = ;σ= A ρ Resistances in series and parallel (links to Unit 2), calculations of the total resistance of circuits with series and/or parallel components 1 1 1 RT = R1 + R2 ; = + RT R1 R2 Definition of the volt as 1 joule per coulomb V2 Power dissipation P=IV ; P= I 2 R ; P = R Definition of resistance; the ohm Potential difference defined as the work done per coulomb of charge transferred between two points. ΔQ Electric current as rate of flow of charge I = Δt Charge, current and potential difference Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 9 10 klm Plot output voltage against position or angle for linear and logarithmic electrical potentiometers Vary output of a LS using a potentiometer and investigate volume vs potentiometer setting. Experiments with meters in series and parallel circuits Designing simple temperature sensor Copyright © 2008 AQA and its licensors. All rights reserved. Electrical variations produced by potential; divider systems and on-off switches. Use of potential divider to control voltage, comparison with the use of a variable resistor. Link with use in microphone/loudspeaker circuit to act as a volume and balance control;. Total pd = sum of pd across series resistor Current conserved at a junction (Kirchoffs law) A simple microscopic explanation of resistance , how thermal energy is generated when charge flows, and how resistance changes with temperature for metals and ntc thermistors Thermistor as a device for controlling temperature The behaviour of ohmic and non-ohmic conductors including a practical investigation of a filament lamp and ntc thermistor Examining components in a box Model transmission line. [Duncan. Exploring Physics and elsewhere] Energy distribution; the desirability of transmitting electrical energy using low resistance cable at a high potential difference and low current. Appreciation of the role of ac transformers. Energy = Pt; kWh and an appreciation of current cost http://micro.magnet.fsu.edu/micro/gallery/superconductor/super.html http://superconductors.org/ Superconductivity Experiment 'Measuring the resistance of two insulators' Experiment 'How the dimensions of a conductor affect resistance' Experiment 'Introduction to resistivity using conducting paper' Experiment 'Measuring electrical resistivity' of wires and liquids(CuSO4) Questions 'Electrical properties' Questions 'Resistivity and conductivity calculations' Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0 Temperature gradient, conductivity of materials, cross sectional area. U-values; Range of U-values of common building materials; Rate of energy transfer = UAΔθ Use to calculate total heat loss for parallel surfaces only. Factors affecting thermal energy transfer by conduction and radiation; (temperature gradient, conductivity of material, cross-sectional area) Energy lost by natural and forced convection: Newton’s laws of cooling under forced conversion; concept of half-cooling time (qualitative links to GCSE knowledge of radioactive decay model) Efficiency of energy conversion in the electrical generators, lamps and motors. Comparison of energy distribution and efficiency for a filament lamp and an energy-efficient lamp. Use of rechargeable cells Efficiency including the calculation of overall efficiency of a multistage process. RevNuff Unit G has a section devoted to thermal conductivity and the analogy with electrical conductivity. Updated Lee’s disc experiments with data logging to facilitate data collection Efficiency of motor (link to Where does the energy go?) Building survey using digital camera with infra red sensor Mechanical equivalent/lead shot demo – Case study relating to hybrid cars Types / examples of lagging Lagging experiments – datalogging opportunities Efficiency of heating with lagging klm Copyright © 2008 AQA and its licensors. All rights reserved. 11 Efficiency of rechargeable cells Comparison of efficiency of energy efficient light bulbs with conventional lamps Context: Storing energy and Energy Efficiency This section is taught in the context of energy conservation in the home; it includes the storage of energy, home insulation and double glazing, and comparisons between conventional filament lamps and modern energy-efficient fluorescent types. Abbreviations used: RevNuff Revised Nuffield Physics (full bib ref to come) AP Advancing Physics materials Possible practical’s at http://www.practicalphysics.org/go/Topic_8.html?topic_id=8 E(1½) Teacher Resource Bank / GCE Physics B / Other Guidance: Physics Keeps us Going / version 1.0