6PH03 Exemplar Material - Script 4

5/27/2018 6PH03 Exemplar Material - Script 4

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Exemplar Script 4


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GCE Physics 2008 marking grids AS Script 4A: Summary of case study or physics-based visitCriterion Mark

Ref Criterion Mark Comment

S1 Carries out a visit OR uses library,consulting a minimum of three differentsources of information (egbooks/websites/journals/magazines/casestudy provided byEdexcel/manufacturers data sheets)

1 Assuming that the Introduction to Green Chemistry is ajournal, then 3 different sources are present

S2 States details of visit venue OR providesfull details of sources of information

1 Details of the sources are given

S3 Provides a brief description of the visitOR case study

1 The study of solar cells is clear

S4 Makes correct statement on relevantphysics principles

1 Reasonable explanation of how a solar cell works

S5 Uses relevant specialist terminologycorrectly

1 Correct use of scientific terminology

S6 Provides one piece of relevantinformation (eg data, graph, diagram)that is not mentioned in the briefingpapers for the visit or case study

1 Allowing for the fact that this is photocopied, the diagramof the solar cell is good. Also table of efficiencies is good

S7 Briefly discusses context (egsocial/environmental/historical)

1 Environmental factors discussed

S8 Comments on implication of physics (egbenefits/risks)

1 Benefits and costs of solar cells are discussed

S9 Explains how the practical relates to thevisit or case study

1 Measurement of the internal resistance of a solar cell inrelation to the energy loss in the cell is discussed

Total marks for this section 9

B: Planning


P1 Lists all materials required 1 List of apparatus givenP2 States how to measure one relevant

quantity using the most appropriateinstrument

1 Ammeter used to measure current

P3 Explains the choice of the measuringinstrument with reference to the scale of

the instrument as appropriate and/or thenumber of measurements to be taken

1 Scale to be used on ammeter discussed

P4 States how to measure a second relevantquantity using the most appropriateinstrument

1 Voltmeter used to measure voltage (potential difference)

P5 Explains the choice of the secondmeasuring instrument with reference tothe scale of the instrument asappropriate and/or the number ofmeasurements to be taken

1 Range to be used on voltmeter discussed

P6 Demonstrates knowledge of correctmeasuring techniques

1 Changing range is an appropriate measuring technique


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P7 States which is the independent and

which is the dependent variable1 Identifies power as the dependent variable and resistance

of the rheostat as the independent variable

P8 Identifies and states how to control allother relevant variables to make it a fairtest

0 Identifies temperature of the cell as an important factor butshould also comment on light intensity

P9 Comments on whether repeat readingsare appropriate in this case

0 Could have repeated the experiment to obtain a secondvalue for the internal resistance. However I and Vvaluescannot be averaged because of different rheostat settings.

P10 Comments on safety 1 Hot lamp consideredP11 Discusses how the data collected will be

used1 Graph of power against resistance and finding resistance

at the point of maximum power transferP12 Identifies the main sources of

uncertainty and/or systematic error1 Connection resistance allowed, but light intensity changes

would be a major problemP13 Draws an appropriately labelled diagram

of the apparatus to be used1 Circuit diagram is correct, although it would have been

preferable to have included some sort of protective

resistor or lamp.P14 Plan is well organised and methodical,

using an appropriately sequenced step-by-step procedure

1 Sequenced step by step procedure given


C: Implementation and Measurements


M1 Records all measurements using thecorrect number of significant figures,

tabulating measurements whereappropriate

1 Significant figures used in the table are appropriate

M2 Uses correct units throughout 1 Units correct throughoutM3 Obtains an appropriate number of

measurements1 7 different values of potential difference is sufficient

M4 Obtains measurements over anappropriate range

0 The range of currents and potential differences usedseems very small. Could a different resistance rheostathave been used?



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D: Analysis

E: Report


A1 Produces a graph with appropriatelylabelled axes and with correct units

1 Axes labelled and units

A2 Produces a graph with sensible scales 1 Data occupies more than half the page in each directionA3 Plots points accurately 1 The plotted points checked are correctA4 Draws line of best fit (either a straight

line or a smooth curve)0 The line of best fit consists of parallel lines in some

places.A5 Comments on the trend/pattern

obtained1 Power increases with resistance, reaches a maximum

point and then decreases with resistance discussedA6 Derives relation between two variables

or determines constant1 Determines maximum power and resistance at maximum

powerA7 Discusses/uses related physics principles 0 No discussion of why the internal resistance is equal to

the external resistance when the power is a maximumA8 Attempts to qualitatively consider

sources of error1 Changes of light intensity caused by the lamps of other

students are discussedA9 Suggests realistic modifications to reduce

error/improve experiment0 Far away from other lights is not enough. Would like to

have seen comment on control of incident lightA10 Calculates uncertainties 0 Lowest value of resistance at a possible maximum point is

10.0 on the graph, but the candidate uses 9.5 . Hencecalculation is not correct

A11 Provides a final conclusion 1 Internal resistance of the solar cell has been found.



R1 Summary contains few grammatical orspelling errors

0 Summary is difficult to understand in some places andthere are spelling mistakes

R2 Summary is structured using appropriatesubheadings

1 Subheadings are given in the summary.


Total marks for this unit 32


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6PH03 Exemplar Material - Script 4