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Mark Scheme (Results)Summer 2018Pearson Edexcel GCSEIn Physics (1PH0) Paper 1F

Edexcel and BTEC QualificationsEdexcel and BTEC qualifications are awarded by Pearson, the UK’s largest awardingbody. We provide a wide range of qualifications including academic, vocational,occupational and specific programmes for employers. For further information visitour qualifications websites at www.edexcel.com or www.btec.co.uk. Alternatively,you can get in touch with us using the details on our contact us page atwww.edexcel.com/contactus.Pearson: helping people progress, everywherePearson aspires to be the world’s leading learning company. Our aim is to helpeveryone progress in their lives through education. We believe in every kind oflearning, for all kinds of people, wherever they are in the world. We’ve beeninvolved in education for over 150 years, and by working across 70 countries, in100 languages, we have built an international reputation for our commitment tohigh standards and raising achievement through innovation in education. Findout more about how we can help you and your students at:www.pearson.com/ukSummer 2018Publications Code 1PH0 1F 1806 MSAll the material in this publication is copyright Pearson Education Ltd 2018

General Marking Guidance All candidates must receive the same treatment. Examiners mustmark the first candidate in exactly the same way as they mark thelast.Mark schemes should be applied positively. Candidates must be rewarded for what they have shown they can do rather than penalisedfor omissions.Examiners should mark according to the mark scheme not accordingto their perception of where the grade boundaries may lie.There is no ceiling on achievement. All marks on the mark schemeshould be used appropriately.All the marks on the mark scheme are designed to be awarded.Examiners should always award full marks if deserved, i.e. if theanswer matches the mark scheme. Examiners should also be prepared to award zero marks if the candidate’s response is not worthyof credit according to the mark scheme.Where some judgement is required, mark schemes will provide theprinciples by which marks will be awarded and exemplification maybe limited.When examiners are in doubt regarding the application of the markscheme to a candidate’s response, the team leader must be consulted.Crossed out work should be marked UNLESS the candidate has replaced it with an alternative response.

Mark schemes have been developed so that the rubrics of each mark scheme reflects thecharacteristics of the skills within the AO being targeted and the requirements of thecommand word. So for example the command word ‘Explain’ requires an identification ofa point and then reasoning/justification of the point.Explain questions can be asked across all AOs. The distinction comes whether theidentification is via a judgment made to reach a conclusion, or, making a point throughapplication of knowledge to reason/justify the point made through application ofunderstanding. It is the combination and linkage of the marking points that is needed togain full marks.When marking questions with a ‘describe’ or ‘explain’ command word, the detailed markingguidance below should be consulted to ensure consistency of marking.AssessmentObjectiveStrandElementCommand WordDescribeExplainAO1*An answer that combines the markingpoints to provide a logical descriptionAn explanation that links identification of apoint with reasoning/justification(s) asrequiredAO2An answer that combines the markingpoints to provide a logical description,showing application of knowledge andunderstandingAn explanation that links identification of apoint (by applying knowledge) withreasoning/justification (application ofunderstanding)AO31a and1bAO32a and2bAO33aAO33bAn answer that combines points ofinterpretation/evaluation to provide alogical descriptionAn explanation that combines identificationvia a judgment to reach a conclusion viajustification/reasoningAn answer that combines the markingpoints to provide a logical description of theplan/method/experimentAn explanation that combines identifying animprovement of the experimentalprocedure with a linkedjustification/reasoning*there will be situations where an AO1 question will include elements of recall of knowledge directly from thespecification (up to a maximum of 15%). These will be identified by an asterisk in the mark scheme.

QuestionNumberAnswer1(a)B 1.0 m/sMarkThe only correct answer is BA 0.1 m/s is incorrect, being 1 metre every 10s, insectcrawling paceC 10 m/s is incorrect, being an Olympic sprinter’s pace,much too fast for ‘walking’D 100 m/s is incorrect, being a very fast sport’s car’s pace(1)AO 1 1QuestionNumberAnswerMark1(b)weight / force(1)(accept circle around weight if not contradicted on answerline)AO 1 2

QuestionNumberAnswer1(c)substitution (1)(F ) 0.10 x 2.0Additional guidanceMark(3)100 x 2 (using 0.10kg 100g)AO 2 1reject 0.10 x 2.02 and the followup evaluation (equation givenshould be used)evaluation (1)0.2(0)correct answer without workinggets 2 marksallow 1 mark total for 2 withany other power of ten, so thatincludes 200 for exampleunit (1)Nseparate unit marknewtons / Newtons acceptlowercase ‘n’for the abbreviated unitaccept kg ms-2accept 200 g ms-2 for 3 marksQuestionNumberAnswerAdditional guidanceMark1(d) direction (1)answers only acceptable in givenorder(2) size (1)AO 2 1or magnitude(Total for Question 1 7 marks)

QuestionNumberAnswerAdditional guidanceMark2(a)(i)recall speed distancetimeaccept any correct rearrangementor use of s, d and t(1)AO 1 1may use v for speed and x fordistanceignore use of trianglesQuestionNumberAnswerAdditional guidanceMark2(a)(ii)substitution (1)(speed) 2200.7(0)allow ecf from part (i) for thismark only(2)evaluation (1)310 (m/s)allow any numbers that round to310 e.g.314award full marks for the correctanswer without workingAO 2 1

Question AnswerNumber2(b)Additional guidancean explanation linking: measure across morethan one (wavelength)(1) divide by the number ofwavelengths (1)Mark(2)use a more accurate device(finer divisions)AO 3 3buse a camera /picture/strobe(light) (so thewaves are not moving)count the number ofwavelengthsmust be talking aboutmeasuring, NOT changing thewavelength etc.Question AnswerNumber2(c)Additional guidanceMark(3)a description to include:AO 1 1 longitudinal – (vibrations)parallel to (direction oftravel) (1) transverse – (vibrations)at right angles to(direction of travel) (1)back and forth (oscillations)/compressions or rarefactionsup and down (oscillations) (connection between)direction of travel with(direction of) vibrations(1)(Total for Question 2 8 marks)

Question AnswerNumber3(a)(i)Additional guidancepoints plotted to within 1small square(10, 60)(1)(20, 37)(1)Question AnswerNumber3(a)(ii)point at 15,55Mark(2)AO 2 1Additional guidancecircled (1)Mark(1)AO 2 1Question AnswerNumberAdditional guidanceMark3(a)(iii)reject tramlining (multiplelines/curves) ignore slightshakiness in drawing(1)Question AnswerNumberAdditional guidanceMark3(a)(iv)less steep(1)ignore all comments aboutheat / the process; thequestion is about thecurveAO 2 1best fit curve passing throughmost of the points seen, apartfrom 15,55 (1)the curve will be above the firstone (starting at the samepoint) / it will take longer tocool down / cools more slowly(1)AO 3 2aQuestion AnswerNumberAdditional guidanceMark3(b)(i)estimates, so we are beinggenerous with this(2)wavelength for object L 84.(0)to 85(.0) (µm) (1)wavelength for object M 93.(0)to 95.(0)(µm) (1)AO 3 2a

Question AnswerNumber3(b)(ii)Additional guidanceobject L and shorter wavelength(1)Mark(1)AO 3 1a(Total for Question 3 8 marks)

Question AnswerNumber4(a)(i)kinetic (1)Question AnswerNumber4(a)(ii)Additional guidanceonlyAO 2 1Additional guidanceMark(1)increase the speed (of spinning) accept (idea of) faster(1)Question AnswerNumber4(b)(i)AO 2 1ignore make it biggerAdditional guidancesubstitution (1)(ΔGPE ) 65 x 10 x 200(1)(adding another incorrectalternative negates)any one ofincrease the mass / weight (ofthe flywheel) (1)MarkMark(2)allow substitution mark with65000 (g)evaluation (1)1.3 x 105 / 130 000 (J)allow 1 mark for answersthat round to 1.3 with anyother power of tendo not allow 13000award full marks for thecorrect answer withoutworkingAO 2 1

Question AnswerNumber4(b)(ii)Additional guidanceMarksubstitution (1)(3)(KE) ½ 65 36(2)AO 2 1squaring (1)362( 1296)using 36 1170 (J)OR 36x2 2340 (J) scores 2marks (apply power of tenerror as well if occurring e.g.117000 (J) gets 1 mark)(completing) evaluation (1)42 120 / 4.2(1) x 104 (J)award full marks for thecorrect answer withoutworkingallow 2 marks for answers thatround to 4.2 with any otherpower of tenomitting ½ gives 84240(J)scores 2 marks

Question AnswerNumber4(c)Additional guidancea description to include 3points from: measure a distance (at thebottom) / use mark(er)s(certain distance apart)(1)(3)AO 2 2use a light gate (or equivalentsensors idea) not over wholeslope for this mark point starting timer (at firstmark(er)) (1)use of video / (speed)camera /interrupts the lightbeam stopping timer (at 2ndmark(er))accept any time measured forthis mp including data loggerOR timer / stopwatchOR measures a time(interval) (1) Mark(use speed) distance/time (1)(Total for Question 4 10 marks)

QuestionNumberAnswerMark5(a)proton(s)(1)AO 1 1QuestionNumberAnswerAdditional guidance5(b)(i)a description referring to:Mark(2)AO 1 1fusion involves comingtogether / joining ofparticles / nuclei / atoms (1)not just ‘fuse together’ that’sjust restating – moreexplanation neededfission involves (larger)particle(s) / nuclei /atomsbreaking up (1)particles etc. coming apart /separatingQuestionNumberAnswer5(b)(ii)Dprotonsno marks if just objects /things joining / coming apartMarkThe only correct answer is DA ‘beta particles’ is incorrect, they are not found in nuclei tofacilitate that repulsionB ‘electrons’ is incorrect, for the same reason as AC ‘neutrons’ is incorrect as they don’t repel each other(1)AO 1 1

QuestionNumberAnswerAdditional guidanceMark5(c)(i)substitution (1)(2)845 0000.0394AO 2 1evaluation (1) 21 000 000answers that round to21 000 0002.1(45) x 107 etc.award full marks for thecorrect answer withoutworkingQuestionNumberAnswerAdditional guidanceMark5(c)(ii)any two from:may quote numbers hereaccept no or lesspollution / no or lessharmful gases etc.(2) fusion power gives (many)more times the energyoutput (for the same massused)no greenhouse gases / CO2emissions (produced withthe fusion alternative)does not lead to globalwarmingno (radioactive) wastedoes not deplete / use upa finite resource (e.g. oil)sustainable referenceoil is running outignore references to costsAO 1 1

QuestionNumberAnswer5(c)(iii)any two from: Additional guidanceMark(2)problem of containment(the fusion gases /isotopes at hightemperatures)(maintaining) hightemperature(maintaining) highpressureAO 2 1(Total for Question 5 10 marks)

Question AnswerNumber6(a)Additional guidanceany two sources from: oil (natural) gascoalnuclear/uraniumMark(2)accept petrol /diesel foroilAO 1 1accept fossil fuel(s) forany of the first three i.e.fossil fuel and oil or coalor gas scores 1 mark butfossil fuel and nuclearscores 2 marksQuestion AnswerNumberAdditional guidanceMark6(b)(i)biofuel / biomass(1)bioenergyAO 3 1bQuestion AnswerNumberAdditional guidanceMark6(b)(ii)must be referring tothe chart, not justrepeating 4bi stem- can’thave greatest/ largestamount by itself(1)Additional guidanceMarklargest area / fraction /percentage (idea)Question AnswerNumber6(b)(iii)windAO 3 1b(1)AO 3 1b