2024 NYJC H1 PHY 8867 P2

NYJC 2024 8867/02/J2Prelim/24 [Turn over NANYANG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 1 CANDIDATE NAME CLASS TUTOR’S NAME CENTRE NUMBER S INDEX NUMBER PHYSICS 8867/02 Paper 2 Structured Questions 10 September 2024 2 hours Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class and tutor’s name in the spaces at the top of this page. Write in dark blue or black pen on both sides of the paper. You may use a HB pencil for any diagrams, graphs. Do not use staples, paper clips, glue or correction fluid. The use of an approved scientific calculator is expected, where appropriate. Section A Answer all questions. Section B Answer any one question. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Section A 1 / 9 2 /10 3 /10 4 /17 5 /14 Section B 6 /20 7 /20 Total /80 This document consists of 23 printed pages.

2 NYJC 2024 8867/02/J2Prelim/24 Data speed of light in free space c  3.00  108 m s−1 elementary charge e  1.60  10−19 C unified atomic mass constant u  1.66  10−27 kg rest mass of electron me  9.11  10−31 kg rest mass of proton mp  1.67  10−27 kg the Avogadro constant NA  6.02  1023 mol−1 gravitational constant G  6.67  10−11 N m2 kg−2 acceleration of free fall g  9.81 m s−2 Formulae uniformly accelerated motion s  21 2ut at v2  u2  2as resistors in series R  R1  R2  … resistors in parallel 1/R  1/R1  1/R2  …

3 NYJC 2024 8867/02/J2Prelim/24 [Turn over Section A Answer all questions. 1 (a) State what is meant by the term accuracy. [1] (b) A trampoline consists of a central section supported by springy material. At t = 0, a girl starts to fall vertically onto a trampoline as shown in Fig 1.1. The girl hits the trampoline and rebounds vertically. The variation with time t of the velocity v of the girl is shown in Fig 1.2. Fig. 1.2 Fig 1.1 springy material girl t / s v / m s1 rebound time

4 NYJC 2024 8867/02/J2Prelim/24 (i) For the motion between t = 0 to t = 0.90 s, 1. Calculate the acceleration. acceleration = m s2 [2] 2. The values obtain ed from both axes ha ve an absolute uncertainty of half of the smallest division. Determine the absolute uncertainty of the value in (b)(i)(1). absolute uncertainty = m s2 [2] 3. Using your answers in parts (a) and (b)(i)(2), comment on the accuracy of of the value in (b)(i)(1). [1] (c) Using Fig 1.2, estimate the maximum compression of the trampoline. maximum compression = m [2] (d) Without further calculation, describe and explain the motion of the girl from t = 1.40 s to t = 1.85 s. [1] [Total: 9]

5 NYJC 2024 8867/02/J2Prelim/24 [Turn over ground tennis ball 2 (a) Fig. 2.1 shows a tennis ball at rest on a horizontal ground. Fig. 2.1 The weight of the tennis ball is W and the normal contact force on the tennis ball is N. A student made the following statement in Fig. 2.2. Fig. 2.2 Explain whether the student’s statement is correct. [1] (b) Fig. 2.3 shows the tennis ball before and after bouncing on the ground. The mass of the tennis ball is 0.062 kg. The tennis ball hits the ground at a speed of 14 m s–1. Fig. 2.3 ground tennis ball W and N are equal and opposite forces, so this is an example of Newton’s third law since action and reaction are equal and opposite.

6 NYJC 2024 8867/02/J2Prelim/24 The resultant force acting on the tennis ball during collision with the ground is F. Fig. 2.4 shows how force F varies with time t during the collision. Fig. 2.4 (i) State Newton’s second law of motion. [1] (ii) Calculate the momentum of the tennis ball just before it hits the ground. Give a unit with your answer. momentum = unit = [2] (iii) Determine the speed v of the tennis ball with which it leaves the ground. v = m s1 [3]

7 NYJC 2024 8867/02/J2Prelim/24 [Turn over (iv) Using your answer in (iii), explain whether the collision is elastic. [1] (v) During collision with the ground, a normal contact force acts on the tennis ball. State and explain whether the magnitude of this normal contact force is greater than, less than, or equal to the normal contact force in (a) when the ball is at rest. [2] [Total: 10]

8 NYJC 2024 8867/02/J2Prelim/24 3 Fig. 3.1 shows an experiment to investigate the extension of two identical springs connected end to end. A student initially measures the length L of the two -spring combination without a load attached. Fig. 3.1 The student adds mass m to the lower spring and measures the new length L of the two-spring combination. The student determines the weight F of the mass added to the spring. The student’s results are shown in Fig. 3.2. m / g F / N L / cm e / cm 0 0 12.0 50 0.49 13.0 100 0.98 13.8 150 1.47 14.8 2.8 200 1.96 15.6 3.6 250 2.45 16.6 4.6 Fig. 3.2 (a) Complete the missing values for the extension e of the spring combination in the table shown in Fig. 3.2. [1] (b) On Fig. 3.3, plot the remaining points on the graph and draw the straight line of best fit. [2] L springs retort stand clamp

9 NYJC 2024 8867/02/J2Prelim/24 [Turn over Fig. 3.3 (c) Determine the gradient of the straight line of best fit. gradient = [1] 0 0.5 1.0 1.5 2.0 2.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 F / N e / cm × × ×

10 NYJC 2024 8867/02/J2Prelim/24 (d) Use your answer in (c) to determine the experimental value for the spring constant k of the two-spring combination. Include an appropriate unit. k = unit = [2] (e) State and explain whether your graph show s that the spring combination obeys Hooke’s law. [2] (f) The student repeats the experiment with a third identical spring added to the bottom of the two springs. State and explain how the elastic potential energy stored in each spring in this three-spring combination would be different from that in each spring in the two-spring combination. [2] [Total: 10]