TJC 2024 H2 Paper 4 Solutions

Name: _____________________________________ CG: ___________ Date: _____________ Marking Scheme for Question 1 No Mark Scheme Mark Score 1(a) d measured to the nearest 0.01 mm with consistent unit Evidence of repeated measurements of d 1 (b) A calculated correctly to correct s.f 1 (e) I recorded to the nearest 0.1 mA with consistent unit. V1 and V2 recorded to the nearest 0.001 V 1 1 (f) Tabulate at least 6 sets of readings with correct d.p for I, V1 and V2. Award 0 marks if < 5 readings are taken. Award 0 marks if assistance is provided in circuit setup. Correct d.p for V1 + V2 Correct column headings with units Note: − 2 marks for table if unable to obtain varying I, V1 and V2 values. 1 1 1 (g) Graph Correct linearization equation. Note: (V1 + V2) against I Correct label of axes and graph should occupy at least half of graph paper. Correct plotted points Gradient coordinates read correctly and correct calculation of gradient. Correct calculation of  with units. 1 1 1 1 1 (i) Sensible method to obtain ratio of cross-sectional areas. e.g. ratio of 1 2 V V . 1 Total 13

No Marking Instructions Mark Score 2(b)(i) L and a recorded to nearest mm or 1 dp in cm or 3 dp in m. 1 2(b)(ii) b recorded to nearest mm or 1 dp in cm or 3 dp in m. b should be between 70 % to 90 % of a Repeat measurement 1 1 2(c)(i) Acceptable explanation 1 2(c)(ii) Uncertainty in b greater than 0.2 cm Percentage uncertainty to 2 sf 1 2(d) K calculated correctly to 3 sf 1 2(e) Correct linearization of eqn Correct expression for gradient 1 1 Total 8

No Marking Instructions Mark Score 3(a)(i) D recorded to nearest 0.01 cm with unit Zero error recorded or evidence of repeat measurement (range of D is with 10%) 1 (a)(ii) d recorded to nearest 0.01 cm with unit. Evidence of repeat measurement 1 (a)(iii) r calculated correctly to correct d.p. with unit 1 (a)(iv) Correct calculation of % uncertainty using sensible value of D and x. (0.03 cm ≤D andx ≤ 0.05 cm) 2 (b)(i) TR calculated correctly to 3 sf with clear working from <t> 1 (b) (ii) TS calculated correctly to 3 sf with clear working from <t>, TS > TR 1 (c) L recorded to the correct d.p. with unit . Evidence of repeat measurement TR calculated correctly to 3 sf with clear working from <t> TS calculated correctly to 3 sf with clear working from <t> (*value of TS larger than TR , otherwise minus 1 mark) 2 (d)(i) Correct calculations of the two k values with correct unit 1 1 (d)(ii) Correct justification of s.f. of k linked to s.f. in r, L and TR (lowest s.f.) 1 (d)(iii) Draw conclusion based on stated criterion. (e.g. not obeyed because % difference of k values > % uncertainty of r in (a)(iii)) 1 (e) (i) All observations plotted and line of best