2021 RI Yr CT Sect B QP

© Raffles Institution 9749 Name: ( ) CT Group: 22S0 RAFFLES INSTITUTION 2021 YEAR 5 TERM 3 COMMON TEST 30 June 2021 H2 PHYSICS RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES Section B INSTRUCTIONS TO CANDIDATES Write your name, index number and CT Group. Write your answers to Section B in the spaces provided on the question paper. You are advised to write all your workings and answers clearly. Marks may be deducted for unclear workings. For Examiner’s Use Section A MCQ / 15 Section B 1 / 10 2 / 11 3 / 11 4 / 11 5 / 12 6 / 11 7 / 14 Deductions Total / 95 This document consists of 19 printed pages.

2 © Raffles Institution 9749 [Turn over Section B (80 marks) 1 An equation that governs gas-flow through a cylindrical tube is given by ( ) 3 12cr p p mZ L RT −= , where c is a unitless constant, r is the internal radius of the tube, p 1 and p2 are the pressures at the ends of the tube, L is the length of the tube, m is the molar mass of the gas (in kg mol−1), R is the molar gas constant (in kg m2 s−2 K−1 mol−1), and T is the thermodynamic temperature of the gas. (a) Show that the SI base unit of pressure is kg m−1 s−2. [1] (b) Determine the SI base unit of the quantity Z. base unit = [2] (c) Experiments on gas -flow through a cylindrical tube are conducted. The pressure difference (p1 − p2) between two points along the tube is recorded as 800 101 Pa by a pressure gauge as shown in Fig.1.1 . However, the manufacturer of the pressure gauge states that its measurements have a percentage uncertainty of 2.5%. Fig. 1.1 p1 p2 pressure gauge

3 © Raffles Institution 9749 [Turn over (i) Determine the absolute uncertainty in the value of (p1 − p2). absolute uncertainty = Pa [2] (ii) Hence, state (p1 − p2), with its uncertainty, to an appropriate number of significant figures in terms of MPa. (p1 − p2) = ± MPa [1] (d)