MARKING SCHEME PHYSICS SCIENCE UNIT P1 ADDITIONAL SCIENCE UNIT P2 MS2 2.00

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1 MS.00 GENERAL CERTIFICATE OF SECONDARY EDUCATION TYSTYSGRIF GYFFREDINOL ADDYSG UWCRADD MARKING SCEME PYSICS SCIENCE UNIT P ADDITIONAL SCIENCE UNIT P JANUARY 008

2 INTRODUCTION The marking schemes which follow were those used by WJEC for the January 008 examination in GCSE Physics Units for Science, Additional Science & Physics. They were finalised after detailed discussion at examiners' conferences by all the examiners involved in the assessment. The conferences were held shortly after the papers were taken so that reference could be made to the full range of candidates' responses, with photocopied scripts forming the basis of discussion. The aim of the conferences was to ensure that the marking schemes were interpreted and applied in the same way by all examiners. It is hoped that this information will be of assistance to centres but it is recognised at the same time that, without the benefit of participation in the examiners' conferences, teachers may have different views on certain matters of detail or interpretation. WJEC regrets that it cannot enter into any discussion or correspondence about these marking schemes.

The conferences were held shortly after the papers were taken so that reference could be made to the full range of candidates' responses, with photocopied scripts forming the basis of discussion.

3 Physics F. Box Box 4 [Geothermal] () Box 3 Box 3 [Biomass] () Box 4 Box [Wave energy] () 3 [additional lines ] 3. (a) (i) C [accept D] (ii) C (iii) A (b) Optical fibres or other suitable answer / e.g. endoscope, communication. [Accept use of domestic renewable energy source for mark 4 Solar wind heat exchanger 3. (a) (i) radiation (ii) radiation (b) Any from: turn down thermostat [or heating] / fit double glazing / hang or close curtains / draft excluders / insulate the loft etc. [not close the doors / windows / turn heating off] 4 4. (a) (i) elium (ii) fusion (b) (i) gravity /gravitation / gravitational force (ii) stable [state] [not doesn t move] accept doesn t get bigger or smaller. 4. (a) (i) 8 (ii) 3 [e.c.f. from (i)] (b) (i) 8 [not 8000] (ii) E (c) Communications, weather or TV or telephones [if qualified], spying etc / space telescope /looking into space / sat nav / GPS [TomTom or Garmin wuth qualification] 6. (a) Indication that wind strength fell [accept answer in terms of power output] (b) (i) 70 MW (ii) Efficiency = e.c.f. 00% ( - subst) = 4.% ( ans) Accept 4% [ marks] 4% [ mark] (c) hydroelectric, solar, geothermal, wave. biofuel, tides, sun [accept hydro]

(a) (i) radiation (ii) radiation (b) Any from: turn down thermostat [or heating] / fit double glazing / hang or close curtains / draft excluders / insulate the loft etc.

4 F 7. F, [C], D, B, [A], E All boxes correct 3; boxes correct ; Any box correct 8. (a) (i) units used = 6 (ans) [no unit penalty (ii) Cost = 6 0 = 60 p [e.c.f. from (i)] (ans) (iii) Takes only half the time [accept uses half the number of units] (b) less energy used in making electricity / lower greenhouse emissions / reduce of fossil fuels / less pollution [if qualified] 4 9. (a) (i) 0. (), 700 () in table (ii) Low power rating / uses less energy [not uses less electricity] (a) As the distance increases the temp decreases () in a non-uniform way () (b) (i) 30 (ii) Mars (c)

from (i)] (ans) (iii) Takes only half the time [accept uses half the number of units] (b) less energy used in making electricity / lower

5 F (i) 4 units (ii) 0 cycles (iii) number of waves (produced) in second [accept 0 wavelengths in one second] (iv) wavespeed Wavelength = (any form) frequency 000 Wavelength = () = 00m 0 3 (a) 336 () and 0 () in the table. () (b) traps / contains air () which is a good insulator () poor conductor [No free electrons mark] (a) (i) Power = voltage current or power current (manip) voltage or (subst) () = current ( subst) current = ( manip) = 00 A (ii) voltage reduced by (factor of) 8 so current increases by 8 times () [or by calculation] [accept current of 4000 A] (b) Keeping current low () reduces heat [or energy] losses () (c) Efficiency = Useful energy transfer 00% total energy input = 00% total energy input Total energy input = ( subst/manip) = 800 MW ( ans) 9 3

() (b) traps / contains air () which is a good insulator () poor conductor [No free electrons mark] 4 6 4 (a) (i) Power = voltage current or power 00 000 000 current (manip) voltage 400 000 or

6 (a) Units used = power (kw) time (h) () [accept without units] Units used = () = 300 () (b) Units used = = 00 () (c) Cost = units used cost per unit Or 300 0p = 30 Money saved = 00[e.c.f.] 0p () = 0 () 00 0p = 0 Methodology [i.e. postscales] () Accuracy () 0 (d) 48 Division or 48 ecf () (e) Reduced use of fuels / less energy used (), reduced number of power stations needed () Reduced emissions of CO into atmosphere / global warming () Reduction in material used in making bulbs () Reduced use of landfill () SO x / acid rain reduction () 3 4

7 F 6 (a) (i) In the first diagram [All] lines moved () to the red / longer wavelength end [of spectrum] () [Allow spectrum stretched] () N.B. light red shifted mark Spectrum stretched mark (ii) moving away from us (iii) Universe is expanding / moving out from a point (b) (i) Lines further towards the red / longer wavelength / greater red shift (ii) Galaxies moving faster 6 7 (a) speed = distance time subst / manip () Factor of () Answer obs () 3 (b) (i) Ray shown directly from A B ( only) Rays from A B, shown reflected off point between A and B or reflections () (ii) [Totally] internally reflected accept TIR (iii) Angle bigger than critical angle or bigger than 4-48º (for glass) () and directed from a more to a less dense medium [or from low speed to high speed of light material] () N.B. (ii) and (iii) marked together. 9

shift (ii) Galaxies moving faster 6 7 (a) speed = distance time subst / manip () Factor of () Answer obs () 3 (b) (i) Ray shown directly from A B ( only) Rays from A B, shown reflected off point

8 Physics F. (i) [m/s] (ii) 8 [m/s] (iii) 30 [s] 3. (i) insulation (ii) Earth (iii) miniature 3 3. (a) (i) 0% [correct answer only] not ½ (ii) cosmic [rays] (iii) radon [gas] (b) (i) Finland (ii) Sweden 4. (a) (i) voltmeter [not: voltameter] (ii) ammeter [not: ampmeter, amp meter] (b) (i) Plots (); line () [no penalty for no (0,0) line must go through (0,0)] Not: Double or rough lines. 3 (ii) 4 V e.cf., i.e the reading from the graph. (iii) answer to (ii) () = numerical ans to (ii) [Ω] () 8. (a) (i) Bismuth/Bi [accept 6 minutes] (ii) Polonium/Po or Bismuth/Bi (iii) Polonium/Po (b) (i) Y (ii) X (c) 00 (); 4 () 4 6. (a) 40 ( subs) = 6 m/s () 70 (b) (i) drag / air resistance / friction [not wind or wind resistance] (ii) Increases /stronger (iii) constant speed /steady speed / terminal velocity / no acceleration (c) () = J () 7 6

(a) (i) voltmeter [not: voltameter] (ii) ammeter [not: ampmeter, amp meter] (b) (i) Plots (); line () [no penalty for no (0,0) line must go through (0,0)] Not: Double or rough lines. 3 (ii) 4 V e.cf.

9 F F-tier 7. (a) 60 = A ( ans) [accept 0 3 A] (b) [e.c.f.] [or equiv] () = 03 A () (c) -tier. (a) Or 40 () = 04 A () 30 () (). [must be rounded down] Power Current = Voltage ( subst) = 0 6 A ( ans) (b) [e.c.f.] [or equiv] () = 03 A () (c) Or 40 () = 04 A () 30 () () (d) Can be reset / quicker acting / more reliable / sensitive [any ] 9 8. (a) More chance of survival [in a collision] Or comparison of values at 0 m/s and 30 m/s [even without conclusion] [must be a reference to the graph] (b) (i) = 7 m [method or answer] (ii) speed = distance [any correct form] Mark together, e.g. 7 used in time (iii) mark in (ii) if nec. 7 () = m/s () 0 (iii) 3-36 mph [e.c.f.] (iv) 40 7% [e.c.f.] If speed < 0 mph must be >96% survival If speed > 0 mph must be 0 survival. 7 7

0 43 (d) Can be reset / quicker acting / more reliable / sensitive [any ] 9 8.

10 F (i) Reasonable health-related [harm] answer () [accept contamination/ harms environment] Reasonable decay time answer () [accept: still active after disposal] (ii) Must be different answers. Any 3 () from:. Implication of lack of containment. Seismic activity / water supply problems 3. Leakage / corrosion / cracking 4. Take off problems [explode / fall back to earth / re-enter atmosphere], cost [No reference to extra-terrestrials]. Ice sheets may melt / global warming 6. Island may be populated in future. (ii) Any suitable responses [3 ] 3 4. (a) X = voltmeter (), Y = ammeter (), Z = diode 3 (b) (i) Up to ~0 6 V zero current () [or equiv.] Current increases (with voltage) () non-uniformly () 3 (ii) Voltage = current resistance 0 0 A () 0 7 Resistance = = 00 = 7 0 Ω () 9 (a) ΔE P = mgδh [in words] Accept PE = mgh Increase in potential energy = 60 0 () = J () (b) (i) = 000 J (ans) e.c.f. (ii) mass speed Kinetic energy = ; accept KE = ½ mv 60 speed KE 8000 = ( subs or for manip eqn eg v = ); m speed = 4 m/s (ans) (c) The weight / gravitational force is greater than () the air resistance () (d) 0 () 0 or J() [e.c.f. from (a)] J () [e.c.f. from (a)] 3 8

Take off problems [explode / fall back to earth / re-enter atmosphere], cost [No reference to extra-terrestrials]. Ice sheets may melt / global warming 6. Island may be populated in future.

11 F 6 (a) (i) The [radio]activity halves () in minutes / this time () [or equiv.] Mass [of radioactive material] to halve. (ii) Stable nucleus ()because there is a balance () between the number of protons and neutrons () [any from 3] (b) (i) [Gamma] radiation detected outside body (); suitable half life () (ii) No. of half lives = 0 () [award for method of calculating no. of ½ lives] or 0 04 () [0 0976%] 8.GCSE.Physics (January 008)/LG 4-Feb-08 9

(ii) Stable nucleus ()because there is a balance () between the number of protons and neutrons () [any from 3]

12 WJEC 4 Western Avenue Cardiff CF YX Tel No Fax exams@wjec.co.uk website:

AQA Level 1/2 Certificate in Physics PAPER 1 SPECIMEN MARK SCHEME. AQA Level 1/2 Certificate in Physics Paper 1 MS

AQA Level 1/2 Certificate in Physics PAPER 1 SPECIMEN MARK SCHEME. AQA Level 1/2 Certificate in Physics Paper 1 MS AQA Level /2 Certificate in Physics PAPER SPECIMEN MARK SCHEME AQA Level /2 Certificate in Physics Paper MS MARK SCHEME Information to Examiners. General The mark scheme for each question shows: the marks