VJC 2026 H3 Physics Prelim

VJC 2026 9814/01/J2Prelim/26 [Turn over VICTORIA JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 3 CANDIDATE NAME CLASS TUTOR NAME PHYSICS 9814/01 Paper 1 22 September 2026 3 hours Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class, Centre number and index number 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. You are advised to spend about 1 hour and 50 minutes on Section A. Section B Answer two questions only. You are advised to spend about 35 minutes on each question in Section B. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use 1 / 6 2 / 13 3 / 14 4 / 10 5 / 17 6 / 20 7 / 20 8 / 20 Total / 100 This document consists of 26 printed pages H

2 VJC 2026 9814/01/J2Prelim/26 Data speed of light in free space c = 3.00 × 108 m s−1 permeability of free space  = 4 × 10−7 H m−1 permittivity of free space  = 8.85 × 10−12 F m−1 . 91 0 1 8 99 10 m F4 − = elementary charge e = 1.60 × 10−19 C Planck constant h = 6.63 × 10−34 J s 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 molar gas constant R = 8.31 J K−1 mol−1 Avogadro constant NA = 6.02 × 1023 mol−1 Boltzmann constant k = 1.38 × 10−23 J K−1 gravitational constant G = 6.67 × 10−11 N m2 kg−2 acceleration of free fall g = 9.81 m s−2 Formulae

3 VJC 2026 9814/01/J2Prelim/26 [Turn over

4 VJC 2026 9814/01/J2Prelim/26 Section A Answer all questions in this section. You are advised to spend about 1 hour 50 minutes on this section. 1 A thorium nucleus decays by the emission of an -particle to form a radium nucleus. This is represented by the nuclear equation: 232 228 90 88Th Ra + α→ The thorium nucleus is initially stationary. (a) (i) Show that =speed of radium nucleus 1speed of α-particle 57 . [1] (ii) Show that =kinetic energy of radium nucleus 1kinetic energy of α-particle 57 . [1] (b) The total energy released in the decay is 4.08 MeV. Assume that all this energy goes into the kinetic energies of the -particle and the radium nucleus. The specific charge (charge per unit mass) of an -particle is 4.81  107 C kg-1. Calculate the speed of the -particle. speed = m s-1 [4] [Total: 6]

5 VJC 2026 9814/01/J2Prelim/26 [Turn over 2 A point mass m is held at the centre of a circular plate of radius r = 20 cm attached to a fixed board. The board is tilted at an angle of 30o to the horizontal, as shown in Fig. 2.1. The point mass is given an initial velocity u = 0.50 m s-1 in the direction shown in Fig. 2.1. (a) Determine the time taken for the point mass to fall off the edge of the circular plate. Ignore the efforts of friction. time = s [5]

6 VJC 2026 9814/01/J2Prelim/26 (b) The circular plate is removed. A solid ball of mass m is released at the top of the sloping face of the board The ball rolls down the sloping board without slipping, as shown in Fig. 2.2. A constant frictional force F exerts a torque  on the ball. By considering the forces on the ball, show that the linear acceleration a of the ball down the slope is 3.5 m s-2. [6]

7 VJC 2026 9814/01/J2Prelim/26 [Turn over (c) A solid cylinder of mass 80 g is released from rest at the top of the board. It rolls down the slope without slipping, with its central axis perpendicular to the slope, as shown in Fig. 2.3. When the cylinder reaches point A, the linear speed v of the cylinder is 1.84 m s-1. Calculate the rotational kinetic energy of the rolling cylinder as it passes point A. rotational kinetic energy = J [2] [Total: 13]

8 VJC 2026 9814/01/J2Prelim/26 3 A parallel plate capacitor has circular parallel plates. The capacitance C of a parallel plate capacitor is given by the equation: = 0 AC d where 0 is the permittivity of free space, A is the surface area of each capacitor plate and d is the separation of the capacitor plates. (a) (i) Express the volt in SI base units. units = [2] (ii) Express the units for the permittivity of free space in SI base units. units = [2] (b) The diameter of the circular capacitor plates is measured to be 6.50 cm and their separation is measured to be 5.42 mm. State and explain which instruments are used for making these measurements. instrument for measuring diameter instrument for measuring separation explanation [2]

9 VJC 2026 9814/01/J2Prelim/26 [Turn over (c) Air is usually an insulator, but if the electric potential gradient is large enough, arcing (sparks) can occur between the capacitor plates. The voltage at which arcing first occurs is known as the breakdown voltage Vb. The capacitor in (b) is connected to a power supply that is designed to deliver a constant current of I = 4.0 A when charging. A student records a time T = 12 minutes 14 seconds for N = 200 sparks to occur. Assume that each sparking event causes the capacitor to fully discharge and the value of the permittivity of air is approximately equal to the permittivity of free space. (i) Show that an expression for the breakdown voltage of air is given by = 0 TdV NAb I . [3] (ii) Use the expression in (c)(i) to determine the value of the breakdown voltage of air. Vb = V [3] (iii) Suggest how the breakdown voltage would change if the experiment is done in a vacuum chamber. Refer to the measurements for T and N in your answer. [2] [Total: 14]

10 VJC 2026 9814/01/J2Prelim/26 4 (a) Describe qualitatively, the results of the Michelson-Morley experiment and its implications for the Ether theory. [2] (b) State briefly in words what you understand by the term time dilation. [1] (c) The star Proxima Centauri is 4.20 light years from Earth. An astronaut travels to the star and back in a spaceship moving at 0.99 c (where c is the speed of light), as measured by a scientist in Mission Control on Earth. Both the astronaut and the scientist are aged 30.0 years at the time of departure of the spaceship. (i) Define a light year [1] (ii) Calculate the time taken for the mission, according to the scientist on Earth. Hence find the age of the scientist when the spaceship returns. age = years [2] (iii) Calculate the time taken for the mission, according to the astronaut on board the spaceship. Hence find the age of the astronaut when the spaceship returns. age = years [4] [Total: 10]