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BBC Bitesize Commissioning Brief – Physics
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Commissioning Brief
GCSE Physics CCEA Revised Specification 2017
Overview
Physics is the study of energy, forces, mechanics, waves, and the structure of atoms and the physical
universe. Students gain an understanding of the role of physics in their everyday lives and the world
around us. It helps them develop skills in exploring hypotheses, evidence, theories and explanations.
Students can also develop transferable skills like observation, modelling, enquiry, problem-solving
and critical analysis. Practical science is a key focus, with the specification listing nine prescribed
practical experiments that students must carry out during the course.
GCSE physics is available to students studying the curriculum with the CCEA exam board. CCEA will make the first award based on this specification in summer 2019. BBC Bitesize currently offers a programme of study for GCSE physics that caters for the AQA, Edexel,
Eduqas, OCR and WJEC exam boards. j
To ensure the resource is relevant and user-friendly for students in Northern Ireland, all written
content currently on Bitesize will be restructured and adapted for CCEA students. New resources are
required for this programme of study to reflect the revised CCEA GCSE physics specification.
Further information on CCEA GCSE Physics can be found here.
BBC Bitesize Commissioning Brief – Physics
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Summary of deliverables
We require the following content for Physics:
o Text: A writer is required to adapt existing Study Guides on Bitesize. Much of the
published content in the Revised Chapters is relevant, but will need adapted to reflect
the 2017 CCEA specification. Some original written content is also required to cover the
latest updates to the specification. The writer you wish to contract must be approved by
the BBC production team.
o Infographics: A minimum of 30 infographics across the commission. Detail of each
infographic to be confirmed by a teacher or education consultant contracted to write
and adapt Revise Chapters.
o Video: Approximately 27 minutes of film / animation across the commission
(Indicatively 9 x 3 minutes). These films will be based on the Prescribed Practical
experiments in Unit 3 of the CCEA specification. Given the nature of the practical
experiments, live action video may be the most appropriate medium. A combination of
live action and animation is also acceptable.
o Social cut: Please note that we require additional social cuts of each of the videos.
These should be square framed, subtitled and under a minute in length.
o Interactive quizzes: Test chapters for each Study Guide (8 - 10 multiple-choice
questions per quiz).
o Bitesize App Content: Flashcards for each Study Guide.
Indicative budget: £60,000
Bitesize Brand Values and Tone
Quality learning resources with high production values, tailored to the needs of the audience
Clear, concise delivery of the key educational points in bite-sized chunks Accessible to every level of academic ability and learning style Factually correct, high-quality and curriculum-relevant Simple, straightforward language Funny, quirky or irreverent tone where appropriate Innovative educational media format
BBC Bitesize Commissioning Brief – Physics
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Audience
The target audience for this commission is 14-16 year old students studying GCSE Physics.
From our audience research, we have found that students:
Enjoy revision tools that are short, snappy and precise
Prefer videos and diagrams to text
Prefer bullet pointed text rather than long paragraphs
Enjoy interaction in learning i.e. quizzes and tests
The Subject CCEA GCSE Physics is comprised of three units of study.
UNIT 1: UNIT 2:
UNIT 3:
Motion, Force, Density and Kinetic Theory, Energy, and Atomic and Nuclear Physics
Waves, Light, Electricity,
Magnetism, Electromagnetism and Space Physics
Practical Skills
(including 9 prescribed practicals)
*For a more detailed breakdown, see Appendix Item A: Suggested Content Breakdown.
Content for Delivery
Bitesize Components
Text o Working with writers that are skilled and knowledgeable about the Physics specification you
will produce text for Revise Chapters. Writers you wish to contract must be approved by
the BBC production team.
o These chapters will hit key learning points and deliver learning outcomes in each of the
Study Guides.
o This is a revision tool and therefore must focus on what students need to know in
preparation for an exam or assessment.
o All Study Guides MUST contain a Revise Chapter.
Infographics o These sit within the Revise Chapters.
o Infographics are core to Bitesize and are used to explain and creatively lay out the structures,
theories or other complex topics students must understand.
iGFX must be supplied in the following formats;
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Original: Adobe Illustrator file with all layers
Desktop: PNG, 624px wide x up to 624px high, 300dpi
Tablet: PNG, 464px wide x up to 464px high, 300dpi
Mobile: PNG, 304px wide x up to 304px high, 300dpi
(All Graphics must adhere to the Bitesize Style Guide, which is available to download from the
commissioning site)
Video / Animation o Age-appropriate originated video or animation, delivering clear learning outcomes
o Video can be presenter-led, narrated or graphically signposted
o BBC Digital and Learning will be responsible for clearing and paying for any music sourced for
production by the contracted company. Please note: any copyrighted material – including
clips, images and/or commercial music must be signposted to the BBC Production Team at
the earliest stage to ensure rights clearance. It is at the BBC’s discretion to agree the use of
any copyrighted material. Clearance confirmation will be given based on value for money
o It may be possible to include archive clips if they are beneficial to learning, subject to
clearance. Archive could come from a range of genres - we can advise what is available from
the BBC
An Education Consultant will advise and offer guidance on the content during each stage of
production.
*For more detail, see Appendix Item B: Video spec for delivery
Test Chapters o All Study Guides must contain a Test Chapter. Multiple-choice questions quizzing testing
students on what they’ve learned in Revise & Video chapters
o Audio clips and stills can be used within the test chapters. Test chapters usually include 8 –
10 questions
BBC Bitesize App o On the Bitesize App, Physics will exist as a series of flashcards. This includes text summaries,
glossary terms, audio and video content, infographics and quizzes
o The App flashcards are based on the study guides content and include a summary card,
multiple choice quiz cards and relevant glossaries. They are a subset of the main content
suitable for exam revision in bullet points and summarise the key points/information in each
study guide, with a maximum word count of 450 characters
*For more detail, see Appendix Item C: Bitesize App Flashcard Content Creation
BBC Bitesize Commissioning Brief – Physics
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What we’re looking for…
Creative Proposal
Companies are invited to submit a creative proposal. Your proposal should include:
Storyboards/creative approach
For this proposal we expect a storyboard inclusive of a first draft script for the prescribed practical:
Ohm’s law. (For more detail, see Appendix Item D). Animation is acceptable but we feel that live
action video may be the preferred medium to demonstrate the nine prescribed practical
experiments detailed in the CCEA specification.
Tell us what your overall creative approach will be to this content and you must include reference to
any expert consultants you’ll use.
Production schedule
Please provide a top-level schedule of major milestones/project management approach.
Note: A project management system will be required (i.e. Trello, Slack, Basecamp or other tool) to
manage the production of the content and to allow the BBC to track the project’s progress and
record feedback.
Indicative budget
Within your indicative budget, you will need to make allowances for all production and content costs.
Writer
A writer is required to adapt existing study guides, write original content where necessary and to
draft scripts for the films / animations. You are free to suggest writers, but they will need to have
approval from the BBC production team before production starts.
Adviser
An education consultant is essential to advise and offer guidance on the content during each stage
of the production. Your education consultant will need to have approval from the BBC production
team before production starts.
User Testing
There should be at least two user-testing sessions during the course of the production. These should
include working with at least two different schools who are teaching Physics.
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Working with the BBC
There will be a minimum of 4 face-to-face meetings during production (this does not include the
project initiation meeting). In addition, we require a weekly content report/update (via phone or
email). The 4 face-to-face meetings will be with the production team in Belfast – so your travel
expenses should be considered within your budgeting.
Project Initiation Meeting – This first meeting will be a chance to meet the production team in
Belfast. We will discuss the editorial scope of the project, confirm the timeline for delivery and hear
content plans and ideas.
Meeting #2 – This meeting will take place at the mid-point of the pre-production process and will
focus on proposed video content (scripts, storyboards, talent, style and tone), and iGFX samples
(looking at approach and style).
o Checks on text style and tone
o Production schedule/milestones
o Formal Input from the Education Consultant and user testing
Meeting #3 – This meeting will be scheduled for the mid-point of the production process and will
assess content produced to date and next steps including:
o Production schedule/milestones
o Formal feedback from the Education Consultant and user testing
Meeting #4 – This final meeting will be scheduled around the end of the production process to focus
on how the content fits together within the Bitesize framework.
o Production schedule/milestones
o Formal feedback from the Education Consultant and user testing
Company and project team profile
We want to hear from companies who are passionate about learning and enthusiastic about creating
content for one of the BBC’s premier online brands.
Audience awareness will also be key; do you know this audience and their needs? Have you
produced content for them before? Can you produce content that will resonate with them?
Please include details on the skills and experience of the key members of your project team.
We would like to see evidence of your capacity to deliver this content.
Links to relevant portfolio examples
Please send links to content you have produced which you think are relevant to this commission.
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Indicative Budget: £60,000
Please provide a budget breakdown to show how you intend to cost the project. Payment schedule
to be agreed upon award of contract. Typical payment might be:
£20,000 on signature of contract
£20,000 mid production
£20,000 upon final delivery
Working together
Who is responsible for what?
You will be responsible for:
Project management and production of deliverables to agreed deadline and budget
Chairing regular production meetings and communicating project plans and status
We will be responsible for:
Sharing project documentation
Collaboration throughout the production and delivery
Enabling access to any relevant BBC archive
Sign-off at milestones on all content, and on final delivery – within an agreed timeframe
Post-production paperwork to be completed in format supplied by BBC (WebasC)
We will be jointly responsible for:
Ensuring the learning outcomes are met
Ensuring that content is best-fit for the Bitesize audience
Quality assurance of content
The BBC Learning team
Emma Dunseith - Executive Producer
Emma McIlveen – Producer
Peter Matassa – Assistant Producer
David Rowney – Assistant Producer
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Schedule/project management
All Bitesize productions follow an iterative development process and we will feed back as
soon as possible on all editorial decisions.
Final delivery and sign off for the project is February 5th 2019
This project is highly dependent on specific delivery dates that will be defined in the contract. As
such we would like you to give particular attention to clause 9 in our standard terms which states
the following:
If you fail or are due to fail to deliver a Deliverable (or any part thereof) due at any stage specified in
Schedule 2 for any reason not directly and solely attributable to the BBC, the BBC shall (without
prejudice to any other rights or remedies available to the BBC under this Agreement or at law) be
entitled to terminate this Agreement
Should this situation arise and the BBC is forced to terminate, the BBC would only be liable to you for
anything delivered prior to termination. For this reason we would ask that you give timeframes and
delivery the highest priority.
The pitching process
Shortlisted companies will be invited to Belfast to pitch their proposals.
(An allowance of £250 toward travel costs to Belfast is available if based outside Northern Ireland)
Learning experience is not a prerequisite, but a thorough understanding of the needs of the
Bitesize audience and clear approach to addressing those needs is expected.
Deadline for submissions, pitch deliverables and selection requirements are outlined below:
Commissioning Schedule
Commissioning brief published Thursday 23rd August 2018
Deadline for creative proposal submission Monday 10th September
Deadline for notification of shortlisted proposals Tuesday 11th September
Pitch meetings (Belfast) Thursday 27th September
Commission decision deadline Friday 28th September
Contract signed Friday 5th October
Project initiation meeting Friday 5th October
Full delivery of commission Tuesday 5th February 2019
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Proposal Deliverable List
Company Overview, Portfolio and Project Team
Project Overview
Creative proposal for Ohm’s law practical
Production Schedule and Project Management approach
Budget Breakdown
Selection The BBC will use the following standard criteria to evaluate the pitches submitted:
Quality of the idea proposed – suitability for Bitesize audience
Prior experience of company
Ability to meet editorial requirements
Core staff experience
Project management / production plan
Pricing / value for money
Presentation of response
Next Steps
All proposals should be submitted via email to [email protected] by Monday 10th September
2018. Please use Submitted Proposal: GCSE PHYSICS as the subject line.
This is an open brief published on the BBC Learning Commissioning website. Please note that this document is for information purposes only and does not form part of a contractual agreement with the BBC. This is a stand-alone new media commission and the BBC will require all rights in the content, worldwide and on all platforms. The commission will be contracted using the BBC’s New Media Rights Framework 2 agreement. Further information on the BBC New Media Frameworks can be found here: http://www.bbc.co.uk/commissioning/technology-online/how-we-work/new-mediarights-framework.shtml
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APPENDIX
Item A: Suggested Content Breakdown
Physics Unit 1
Topic
Study Guide
Potential Pages
Motion
1. Distance and
displacement
Definitions of distance and displacement
Examples of vector and scalar quantities
Speed, velocity and acceleration
Prescribed practical (P1): how the average speed of an object moving down a runway depends on slope of runway
2. Graphs and motion
Distance-time graphs
Speed-time graphs
Displacement-time graphs
Velocity-time graphs
Forces 1. Newton’s laws
Definition of force
Examples of balanced and unbalanced forces
Newton’s 1st and 2nd laws
Unbalanced forces, mass and acceleration
2. Mass and weight
What is mass?
What is weight?
The acceleration of free fall
Gravity and vertical motion.
3. Hooke’s law
Definition of Hooke’s law
Formula for Hooke’s law
Prescribed practical (P2): how the extension of a helical spring depends on the applied force
4. Pressure Definition of pressure
Pressure in a range of everyday situations
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5. Moment of a force What is a moment of force? How is it measured?
The principle of moments.
Prescribed practical (P3): investigating the principle of moments
6. Centre of gravity Locating the centre of gravity in objects
Equilibrium and stability
Density 1. Measuring density
Introduce concept of density
Regularly shaped objects
Irregularly shaped objects
Graph of mass against volume
Prescribed practical (P4): the relationship between the mass and volume of liquids and regular solids
2. Kinetic theory
Explanation of density using kinetic theory
Solids, liquids and gases
Energy 1. Forms of energy Forms of energy
Principle of the conservation of energy
2. Energy resources Non renewable resources
Renewable resources
Advantages and disadvantages of different energy resources
The Sun
3. Energy efficiency Definition of energy efficiency
Formula
4. Work Force causing movement
Calculating work done
Work and energy
Power
Prescribed practical (P5): investigating personal power.
5. Energy definitions Kinetic energy
Gravitational potential energy
6. Heat transfer Conduction
Convection
Radiation
Global warming
Examples of heat transfer i.e. vacuum flasks
Atomic and nuclear physics
1. The structure of the atom
The model of atomic structure
Rutherford’s nuclear model
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2. The structure of the nucleus
Protons, neutrons and electrons
Atomic number and mass number
Isotopes
3. Radioactive decay Alpha, beta and gamma radiation
Alpha, beta and gamma decay
Blocking alpha, beta and gamma radiation
Background activity 4. Dangers of radiation Cell damage as a result of radiation
Effects of alpha, beta and gamma radiation on humans
Safety procedures when handling radioactive material
Half-life: defining, calculating and determining from graphs
5. Uses of radioactivity In industry
In medicine
In agriculture
Radioactive tracers
6. Nuclear fission As a form of energy
How it occurs
Political, social and ethical issues
Arguments for and against
7. Nuclear fusion Description
Potential as an energy source
ITER
Physics Unit 2
Topic
Study Guide
Potential Pages
Waves
1. Types of waves
Longitudinal waves
Transverse waves
Describing waves 2. Frequency, wavelength and amplitude
Meaning
Calculating
Extracting from graphical data
Calculating wave velocity
3. Reflection and refraction
Plane barriers and plane boundaries
Ripple tanks
Computer modelling and simulation
Reflection and refractions of water
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waves
Reflection and refraction of light
4. Echoes, sonar and radar
Applications of echo
The echo principle
Definition of ulstrasound
Applications of ultrasound technology
Use of sonar to detect objects underwater
Radar
5. Electromagnetic waves
The electromagnetic spectrum
Wavelength and frequency
Dangers of electromagnetic waves
Light 1. Reflection of light Use of a plane mirror
Angles of incidence and reflection
The law of reflection
Locating images
2. Refraction of light Definition
Angles of incidence and refraction
Prescribed practical (P6): use a ray tracing technique to measures angles of incidence and refraction as a ray of light passes from air into glass
3. Dispersion of white light
Different speeds of light in prism
Critical angle
Total internal reflection
Optical fibres
4. Lenses Converging and diverging lenses
Drawing a ray diagram
The human eye
Long sightedness
Short sightedness
Corrective lenses
Electricity 1. Conductors and insulators
Difference between conductors and insulators
Flow of electrons
Conductors and insulators in simple circuits
Standard symbols
2. Electric charge flow Cell polarity
Current, charge and time 3. Ohm’s law Prescribed practical (P7): Ohm’s law
4. Resistance Voltage, current and resistance
Filament lamp
Prescribed practical (P8): Resistance and length
5. Series and parallel circuits
Current and voltage in series and parallel circuits
Hybrid circuits
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Calculating resistance in series and parallel circuits
Prescribed practical – factors affecting resistance
6. Electricity in the home Electrical energy
Electrical power
Three equations for power
Paying for electricity
Switches
Plugs and fuses
Earth wire, live wore, insulation
Magnetism and electro-
magnetism
1. Magnetic fields Field pattern around a bar magnet
Field pattern due to current-carrying coil
Factors affecting the strength of a magnet
Prescribed practical (P9): Investigating the factors affecting the strength of an electromagnet.
2. The motor effect Force on a current-carrying conductor in a magnetic field
Fleming’s left-hand rule
The turning effect
3. A.C and D.C Differences between ac and dc
Sources
Waveforms
4. Electromagnetic induction
Demonstrate EMI
Lenz’s law
Faraday’s iron ring experiment
5. Generation and transmission of electricity
AC generators
Constructing a step-up/step-down transformer
Turns-ratio equation
Step-up/step down transformers role in transmission of electricity
Space physics 1. The Solar System Main features
Order of planets
Satellites
2. Stars Formation
Life cycle
Death of a star
Supernovae
Black holes
3. The Sun Evidence for hydrogen, helium etc in the sun
Fraunhofer’s lines
The Doppler effect
4. The Universe Origin
The Big Bang Theory
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Red shift
CMBR
5. Space travel Evidence for planets outside our solar system
Determining the existence of life on other planets
Possibilities and limitations of space travel
Light years
Physics Unit 3:
Topic
Study Guide
Potential Pages
Practical skills
Practical skills
Planning an investigation
Carrying out an investigation
Analysing experimental data
Drawing conclusions from an experiment
Physics: Prescribed practical experiments (included in Unit 3 or within
the relevant Study Guide).
Prescribed practical
experiments
Motion > Calculating speed, velocity and acceleration P1: using simple apparatus, including trolleys, ball-bearings, metre rules, stop clocks and ramps, to investigate experimentally how the average speed of an object moving down a runway depends on the slope of the runway measured as the height of one end of the runway (ICT resources could be used to process the measurements and analyse the data).
Forces > Hooke’s law
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P2: to investigate experimentally the extension of a spring and how it is related to the applied force, and recall that the extension of a spring is directly proportional to the force applied, provided that the limit of proportionality is not exceeded.
Forces > The moment of a force P3: to plan and carry out experiments to verify the Principle of Moments using a suspended metre rule and attached weights or a pivoted beam and square weights.
Density > Measuring density P4: to investigate experimentally the relationship between the mass and volume of liquids and regular solids, and analyse and interpret the data gathered.
Energy > Work P5: to plan and carry out experiments to measure personal power, either by measuring the time taken to climb a staircase or performing a number of step-ups to a platform.
Light > Refraction of light P6: to use ray tracing to measure the angles of incidence and refraction when light is refracted by a glass block; to demonstrate understanding that the angles of incidence and refraction are measured from a line at right angles to the glass surface known as the normal; and to use the measurements taken to plot a graph of angle of incidence against angle of refraction to show that they are related
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but not proportional.
Electricity > Ohm’s law P7: using a voltmeter to measure the voltage across a metal wire and an ammeter to measure the current passing through the wire, and: - demonstrate understanding that the temperature of the wire is kept constant using a switch and small currents; - demonstrate understanding of the need to obtain sufficient values of voltage and current so that a voltage–current characteristic graph (V-I graph) can be plotted, with voltage on the y-axis and current on the x-axis; - recall that the V-I graph is a straight line that passes through the origin; and - recall that this shows that the current and voltage are proportional for a metal wire at constant temperature, and that this is known as Ohm’s law.
Electricity > Resistance P8: to investigate experimentally how the resistance of a metallic conductor at constant temperature depends on length and obtain sufficient values to plot a graph of resistance (y-axis) and length (x-axis), recalling that: - the graph is a straight line that passes through the origin; and - this shows that for a metal wire at constant temperature the resistance and length of wire are proportional.
Magnetism and electro-
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magnetism > Magnetic field P9: to investigate, describe and recall how the strength of the magnetic field depends on the current in the coil, the number of turns in the coil and the material used as the core of the coil.
Item B: Video Spec for Delivery
VIDEO
Deliver on a hard drive (exFAT) two formats of each video (one compressed and one uncompressed).
Compressed:
Container format: .mp4 or .mov
Maximum file size, 50GB
Video Codec: H.264 / QuickTime
If your system gives you the option to choose between baseline, main and high profile for H264
export, high is preferred.
Frame size: 1920 x 1080
Frames per second: 25 (progressive scan)
Bit rate/ Quality: Constant/100%
Audio
Codec: AAC
Channels: Stereo
Bit rate: 320 kbps
Sample rate: 48 KHz
Sample depth: 16 bit
For online there is no set level – if it is consistent and you can hear the voice over the music mix and
it is not too low or distorted, it is fine.
Uncompressed:
Deliver an uncompressed version on separate channels.
This can be the source files used within the editing system, with Video, Voice, Music, SFX and
Graphics on separate channels.
Graphics must be rendered on separate channel for translation.
Video Codec is AVC Intra Class 100. Premiere and FCP you can use the DPP AS-11 HD export
setting.
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If delivering animation, use the uncompressed Animation Codec.
H264 source footage from DSLRs is acceptable.
Please refer to this link for output https://www.digitalproductionpartnership.co.uk/what-we-
do/technical-standards/programme-delivery-standards/
MUSIC
Commercial music should only be used in the videos if there is an editorial reason to do so and this
needs to be agreed with the BBC prior to inclusion.
SUBTITLES
To deliver an XML for subtitles for each video (English SDH)
Using a form of XML called TTML EBU-TT-D (Time Text Markup Languages)
Section 26 - http://bbc.github.io/subtitle-guidelines/
For file format please refer to this link http://bbc.github.io/subtitle-guidelines/ from section 23.
There are other useful guides in this file but a basic style guide and example will be supplied later.
DOCUMENTATION
The following Post Production Documentation must be completed on the following templates and
returned as complete within seven days of the delivery date:
Metadata for each video written by a teacher/educational consultant
2 x post production transcript for each piece of video – one timecoded and one without
timecode
Item C: Bitesize App Flashcard Content Creation
Outline of work
All content for the app should be based on the main Study Guide content. For each subject the app
will include a deck of flashcards suitable for GCSE students’ exam revision.
Each deck of flash cards will include:
- Summary cards outlining the main points of the Study Guide
- Multiple choice quiz cards, including feedback
- Relevant glossary cards
Summary cards
Each card is a list of bullet points which summarises the key points/information provided in the
Study Guides on BBC Bitesize. The maximum word count per card is 450 characters (including
spaces).
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Each deck of cards must contain at least one summary card. You can use more summary cards,
separating topics on different cards.
Example
Here are two examples of concise information from Biology and English literature summary cards on
the Bitesize app.
Quizzes
There are five quiz questions per flashcard deck. These questions should all be multiple-choice with
3 possible answers that relate to the topic you have written about.
Questions from the Study Guide can be used but there should be two original questions (reuse up to
three from the study guide).
Provide one piece of meaningful feedback (which offers further explanation) for the CORRECT
answer. This should be one sentence, which further explains the answer and should be useful for
students who get the answer wrong.
Glossary cards
There are a minimum of two glossary terms per deck.
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Example
Glossary term Definition
direct current
Direct current is the movement of charge through a conductor in one direction only.
Item D: Prescribed Practical P7 – Ohm’s law Ohm’s Law states that:
The potential difference (voltage) across an ideal conductor is proportional to the current through it.
The constant of proportionality is called the “resistance”, R.
Resistance can be calculated using V = I x R (R = V / I )
where V is the potential difference (Volts) between two points which include a resistance R (Ohms). I
is the current (Amps).
Apparatus and materials
Ammeter (1 amp), DC
Voltmeter (5 volt), DC
Eureka wire (34 SWG), 10-cm length
Power supply, low voltage, DC
Leads, 4 mm, 6
Crocodile clips, 2
Rheostat (10 ohms, at least 1A)
(A Rheostat is a variable resistor)
Procedure
1. Set up the circuit shown. The length of Eureka wire acts as the resistance in the circuit.
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2. By adjusting the power supply, you can vary the potential difference (p.d.) across the Eureka wire.
The ammeter will show corresponding values of the current through the wire. Keep the current
small so that the temperature of the wire does not increase. (Adjust the rheostat at the beginning
and then keep it constant.) Record a series of values of p.d. and current.
3. Calculate the ratio of p.d./current for each pair of values. Record in the table.
4. Draw a graph to represent the same data. Calculate (and check) the value for resistance from the
graph.
Potential Difference (V) Current (I) Resistance (R)
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The independent variable is normally the potential difference and so it could be plotted along the x-
axis. The resultant current, the dependent variable, would be plotted on the y-axis.
This would show how the current varies with potential difference.
However, the ratio p.d./current is important to us, and so the axes would have to be reversed if the
ratio were needed from the slope of the graph.
The straight-line graph through the origin indicates that the current is proportional to the potential
difference driving it.
It is this proportionality which is Ohm’s law.
Risk Assessment:
Make sure there are no broken wires or loose connections or terminals in your set up and
equipment.
Do not remove or insert any wires while the power supply is switched on.
Ensure you keep the power supply turned to a low value to prevent the bulb from blowing.
(Please note: Bitesize currently hosts a video on Ohm’s law for National 5 students in Scotland –
however, the video for this commission MUST be focused on showing pupils how to set up and
conduct their own experiment as part of their practical assessment.)
