2013 MJC H2 Physics P3

This document consists of 24 printed pages                     MERIDIAN JUNIOR COLLEGE Preliminary Examination Higher 2 _______________________________________________________________________ H2 Physics 9646/3 Paper 3 24 September 2013 2 hours _______________________________________________________________________ Class Reg Number Candidate Name _____________________________ READ THESE INSTRUCTIONS FIRST This booklet contains Sections A and B of the Preliminary Examination Paper 3. Do not open this booklet until you are told to do so. Section A Answer all questions. Section B Answer any two questions. You are advised to spend about one hour on each section. Write your answers on this question booklet in the blanks provided. INFORMATION FOR CANDIDATES The number of marks is given in brackets [ ] at the end of each question or part question. Marks will be deducted if units are not stat ed where necessary or if answers are not quoted to the appropriate number of significant figures. All working for numerical answers must be shown. You are reminded of the need for good English and clear presentation of your answers. Examiner’s Use Section A Q1 /10 Q2 /10 Q3 /12 Q4 /8 Section B Circle the questions you have attempted Q5 /20 Q6 /20 Q7 /20 Deductions Total /80

Preliminary Examination Meridian Junior College 24 September 2013 JC2 H2 Physics 2013   2   Data speed of light in free space c = 3.00 x 108 m s-1 permeability of free space o = 4 x 10-7 H m-1 permittivity of free space ε0 = 8.85 x 10-12 F m-1 = (1/(36)) x 10-9 F m-1 elementary charge e = 1.60 x 10-19 C the Planck constant h = 6.63 x 10-34 J s unified atomic mass constant u = 1.66 x 10-27 kg rest mass of electron me = 9.11 x 10-31 kg rest mass of proton mp = 1.67 x 10-27 kg molar gas constant R = 8.31 J K-1 mol-1 the Avogadro constant NA = 6.02 x 1023 mol-1 the Boltzmann constant k = 1.38 x 10-23 J K-1 gravitational constant G = 6.67 x 10-11 N m2 kg-2 acceleration of free fall g = 9.81 m s-2 Formulae uniformly accelerated motion s = ut + 1 2 at2 v2 = u2 + 2as work done on/by a gas W = pV hydrostatic pressure p = gh gravitational potential  =  Gm r displacement of particle in s.h.m. x = xo sin t velocity of particle in s.h.m. v = vo cos t =   22 o -x x mean kinetic energy of a molecule of an ideal gas E = 3 2 kT resistors in series R = R1 + R2 + … resistors in parallel 1/R = 1/R1 + 1/R2 + … electric potential V = 04 Q r alternating current/voltage x = xo sin t transmission coefficient T  exp(-2kd) where k =   2 2 8( )mU E h radioactive decay x = xo exp(-t ) decay constant  = 1 2 0.693 t

Preliminary Examination Meridian Junior College 24 September 2013 JC2 H2 Physics 2013   3   Section A Answer all the questions in this section. 1 (a) An object is thrown vertically upwards with initial velocity v near the surface of Earth. Air resistance can be neglected. Sketch labelled graphs on the axes below to show how (i) the velocity, and (ii) the acceleration of the object, varies with time. Mark on the graphs the time, t1, at which the object reaches maximum height and the time, t2, at which it returns to its original position. [3] (i) (ii) (b) When air resistance is not negligible, the object will experience drag force in motion. Sketch on the velocity – time graph in (a)(i) above, how the velocity of the object varies with time when air resistance is present. Label this sketch B. [2] velocity / m s-1 time / s acceleration / m s-2 time / s

Preliminary Examination Meridian Junior College 24 September 2013 JC2 H2 Physics 2013   4   (c) A water fountain shoots a jet of water at 5.0 m s -1 towards a target a distance away as shown in Fig 1.1. Fig 1.1 (i) State the relationship of vertical displacement, sy, and horizontal displacement, sx, in terms of t and . [2] (ii) Hence, determine the required projection angle  of the jet of water for it to hit the target. You may wish to use the following relationship: 2 2 1 1t a ncos    = …………………… ° [3]    0.80 m 1.00 m 5.0 m s-1 target

Preliminary Examination Meridian Junior College 24 September 2013 JC2 H2 Physics 2013   5   2 Two rubber balls are moving toward each other in an elastic head-on collision as shown in Fig 2.1. The mass of ball A and B are 1.7 kg and 1.6 kg respectively. Fig 2.1 (a) Given that the initial speed of ball A and ball B are 10.0 m s -1 and 3.0 m s -1 respectively before collision, determine the final speed and direction of the balls after collision. Final speed of ball A = ….….…………….… m s -1 Direction of travel of ball A = ………………………….… Final speed of ball B = .….……………….… m s -1 Direction of travel of ball B = ………………………….… [3] Ball A Ball B

Preliminary Examination Meridian Junior College 24 September 2013 JC2 H2 Physics 2013   6   (b) (i) Given that the two balls are in contact for 10.0 ms during collision, draw on the same axes below, the momentum-time graph for ball A and ball B, before, during and after the collision. [2] (ii) Sketch on b(i) to show how the total momentum varies with time. [1] (iii) State and explain whether the total kinetic energy remains constant throughout the entire duration of impact. .................................................................................................................................... .................................................................................................................................... ............................................................................................................................ [2 ] (iv) If the collision is an inelastic one, state and explain how the speeds of the balls after the collision will differ from your answers in (a). .................................................................................................................................... .................................................................................................................................... ............................................................................................................................. [ 2]                     Time / ms Momentum / N s

Preliminary Examination Meridian Junior College 24 September 2013