TMJC MYE 2024 Section B questions

CANDIDATE NAME ( ) CIVICS GROUP _________________________________________________________________________ H2 PHYSICS 9749 28 June 2024 2 hours 30 mins Candidates answer on the Question Paper. No Additional Materials are required. Section B: Structured Questions READ THESE INSTRUCTIONS FIRST Write your name and Civics Group in the spaces at the top of the page. Write in dark blue or black pen on both sides of the paper. You may use an HB pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. The use of an approved scientific calculator is expected, where appropriate. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. You are to spend 2 hours 30 mins on Section B. ______________________________________________________________________________ This document consists of 27 printed pages and 1 blank page. TAMPINES MERIDIAN JUNIOR COLLEGE JC2 MID-YEAR EXAMINATION For Examiner’s Use Percentage Section A / 15 Section B 1 / 10 2 / 10 3 / 9 4 / 16 5 / 10 6 / 10 7 / 15 8 / 10 9 / 10 Deductions Subtotal Section A&B / 115 / 100

2 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics Data speed of light in free space c = permeability of free space o = permittivity of free space ε0 = = elementary charge e = the Planck constant h = unified atomic mass constant u = rest mass of electron me = rest mass of proton mp = molar gas constant R = 8.31 J K−1 mol−1 the Avogadro constant NA = the Boltzmann constant k = gravitational constant G = acceleration of free fall g = 813.00 10 m s − 714 10 H m −− 12 18.85 10 F m−− ( )( ) 911/ 36 10 F m −− 191.60 10 C− 346.63 10 J s− 271.66 10 kg− 319.11 10 kg− 271.67 10 kg− 23 16.02 10 mol − 23 11.38 10 J K−− 11 2 26.67 10 N m kg−− 29.81 m s−

3 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics Formulae uniformly accelerated motion s = ut + at2 v2 = u2 + 2as work done on / by a gas W = pV hydrostatic pressure p = gh gravitational potential  = temperature T /K = T /°C + 273.15 pressure of an ideal gas p = mean translational kinetic energy of an ideal gas molecule E = kT displacement of particle in s.h.m. x = xo sin t velocity of particle in s.h.m. v = vo cos t =   electric current I = Anvq resistors in series R = … resistors in parallel = … electric potential V = alternating current / voltage X = xo sin t magnetic flux density due to a long straight wire B = magnetic flux density due to a flat circular coil B = magnetic flux density due to a long solenoid B = radioactive decay x = decay constant = 1 2 GM r− 21 3 Nm c V 3 2 22 oxx − 12RR++ 1 / R 121/ 1/RR++ 04 Q r 0 2 d   I 0 2 N r  I 0n I ( )0 expxt −  1 2 ln2 t

4 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics Section B: Structured Questions Answer all the questions in the spaces provided. 1 (a) State Newton’s law of gravitation. ……….………………………………………………………………………........................ ……….………………………………………………………………………........................ …………………………………………………………………………….................... [1] (b) A moon is in a circular orbit of radius r about a planet of mass M. Assume that the planet and the moon are point masses isolated in space. Show that the orbital period T of the moon is given by the expression 23 2 4 rT GM = where G is the gravitational constant. Explain your working. [2]

5 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics (c) Fig. 1.1 shows the planet Mars and the orbits of its two moons, Phobos and Deimos. Deimos has an orbital radius of 23 500 km and takes 30.3 hours to orbit Mars, while Phobos takes 7.7 hours to orbit Mars. Assume the moons orbit Mars with circular orbits. Fig. 1.1 (not to scale) (i) Determine the orbital radius of Phobos. orbital radius = ……………………. m [2] (ii) Hence, or otherwise, determine the orbital speed of Phobos. orbital speed = ………………… m s−1 [2] Mars Phobos Deimos

6 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics (d) The mass of Phobos is 9.6 × 1015 kg and the mass of Mars is 6.4 × 1023 kg. Determine the total energy of Phobos in its circular orbit around Mars. total energy = ………………… J [2] (e) The total energy of Phobos is gradually decreasing due to a gravitational interaction between Phobos and the surface of Mars. State how this decrease in the total energy will affect the kinetic energy of Phobos. ……….………………………………………………………………………........................ ……….………………………………………………………………………........................ …………………………………………………………………………….................... [1]

7 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics 2 An experiment set -up to determine the speed of sound in air is shown below in Fig . 2.1. A loudspeaker connected to a variable frequency signal generator produce sound waves that are directed towards a metal reflector. A microphone connected to a C.R.O is used to detect positions of nodes and antinodes. Fig. 2.1 (a) Explain why a stationary wave is formed between the loudspeaker and reflector. ……….………………………………………………………………………........................ ……….………………………………………………………………………........................ ………………………………………………………………………………………………… ……….………………………………………………………………………........................ …………………………………………………………………………….................... [3] (b) Explain why a node is formed at the position of the reflector. ……….………………………………………………………………………........................ ……….………………………………………………………………………........................ ……….………………………………………………………………………........................ …………………………………………………………………………….................... [2] (c) It is assumed that an antinode is formed at the position of the loudspeaker. On Fig. 2.1, sketch a possible stationary wave profile with the position of the microphone being a node. [2] C.R.O loudspeaker reflector

8 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics (d) At a certain frequency, the microphone detected two adjacent nodes to be 0.200 m apart. When the frequency increased by 480 Hz, the distance between two adjacent nodes decreased to 0.125m. Calculate the speed of sound in this experiment. speed = ……………… m s−1 [3]

9 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics 3 (a) State the first law of thermodynamics. …………………………………………………………….……………………………….….. …………………………………………………………….…………………………………... …………………………………………………………….……………………………. [2] (b) A liquid of mass 3.6 kg and specific heat capacity 15 6 J kg−1 K−1 is heated from its initial temperature of 60 °C until it just reaches its boiling point temperature of 86 °C. The mass and volume of the liquid remains constant during the heating. (i) Calculate the heat supplied to the liquid. heat supplied = ………………… J [2] (ii) State the increase in internal energy of the liquid. increase in internal energy = ………………… J [1]

10 Tampines Meridian Junior College 2024 JC2 Mid-Year Examination H2 Physics (c) The liquid in (b) is heated at its boiling point until all the liquid is turned into vapour. The process takes place at a constant atmospheric pressure of 1.01 × 10 5 Pa. The density of the liquid and the vapour is 840