IFYPH003 Physics THE NCUK INTERNATIONAL FOUNDATION YEAR IFYPH003 Physics Examination Exemplar Time Allowed 2 hours 40 minutes 1 1 INSTRUCTIONS TO STUDENTS Questions 1-13 Answer ALL questions. These questions carry 40 marks in total (40% of the exam marks). Questions 14-18 Answer 3 questions ONLY. These questions carry 60 marks in total (60% of the exam marks). The marks for each question are indicated in square brackets [ ]. Formulae are included in the front of the examination booklet. Graph paper will be provided. An approved calculator may be used in the examination. Show ALL workings in your answer booklet. Examination materials must not be removed from the examination room. State the units where necessary. Where appropriate, working should be carried out to 4 significant figures and answers given to 3 significant figures. DO NOT OPEN THIS QUESTION PAPER UNTIL INSTRUCTED BY THE INVIGILATOR Exemplar © NCUK Ltd. 2021 Page 1 of 16 IFYPH003 Physics Data, formulae and relationships Data Speed of light in a vacuum Gravitational constant Acceleration of free fall Gravitational field strength Electronic charge Electronic mass Proton rest mass Electron-volt Planck constant Unified atomic mass unit Molar gas constant Boltzmann constant Permittivity of free space Coulomb Law constant Avogadro Constant Absolute temperature c = 3.00 10 8 m s – 1 G = 6.67 10 – 11 N m 2 kg – 2 g = 9.81 m s – 2 (close to the Earth) g = 9.81 N kg – 1 (close to the Earth) e = – 1.60 10 – 19 C me = 9.11 10 – 31 kg mp = 1.67 x 10-27 kg 1 eV = 1.60 10 – 19 J h = 6.63 10 – 34 J s u = 1.66 10 – 27 kg R = 8.31 J K – 1 mol – 1 k = 1.38 10 – 23 J K-1 o = 8.85 10 – 12 F m – 1 k = 1 / ( 4 o ) = 8.99 10 9 N m 2 C – 2 NA = 6.02 10 23 mol-1 T/K = θ/ºC+ 273.2 Rectilinear motion For uniformly accelerated motion =u+at s=ut+½at2 2= u2+2as s = [½(u + v)] t Materials and Elasticity Density ρ = m/V Young's modulus E For a spring F = -kx Energy E = ½Fx = ½kx2 Pressure change Δp = ρgΔh FL = σ/ε Ae Forces and moments Moment of F about O = F (Perpendicular distance from line of action of F to O) Dynamics and Energy Kinetic Energy Ek = ½mv2 Gravitational Potential Energy Ep = mgh Exemplar (near Earth’s surface) © NCUK Ltd. 2021 Page 2 of 16 IFYPH003 Physics Newton’s Law (for constant mass) F mam Impulse F t = p Power P=F p t t Radioactive decay and the nuclear atom Activity A=N Half-life Radioactive decay t ½ = ln 2 A A0 e t N N 0e t Electric current and potential difference Work Q t V R I W QV IVt Electric power P = I 2 R = V2/R = IV Electric current Resistance I Electrical circuits RA L Resistivity Resistors in series R=R1+R2+R3 Resistors in parallel Terminal potential difference 1 1 1 1 R R1 R2 R3 V=–Ir Heat Change of state: Q = L m Heating and cooling: E mc Change of internal energy: U = Q + W Equation of State for ideal gas pV nRT pV NkT Exemplar © NCUK Ltd. 2021 Page 3 of 16 IFYPH003 Physics Circular motion and oscillations Angular speed t r Centripetal acceleration a Period T 2 r = rω2 1 2 f Simple Harmonic Motion Displacement x A sin(t ) Acceleration a = -ω2 x Velocity v A cos(t ) = ± ω √( A 2 - x 2) For a simple pendulum T 2 l g For a mass on a spring T 2 m k Waves, Wave Motion and Interference Malus’ law I = Iocos2ϴ Wave speed v = fλ Young's slits = Diffraction grating / d sinθ = nλ Gravitational fields Mm r2 Universal Law of Gravitation F G Gravitational field strength g=F/m Gravitational potential V=W/m Electric fields F Coulomb’s law Q1Q2 4 0 r 2 Electrical potential V = Q/(4πεor) Electric field strength E = F/Q Exemplar © NCUK Ltd. 2021 Page 4 of 16 IFYPH003 Physics Q 4 0 r 2 1 For radial field E For uniform field E=V/d (in free space or in air) Capacitance Capacitance C=Q/V Energy stored W = ½ C V 2 = ½ QV = ½ Q2/C Capacitors in parallel C=C1+C2+C3 Capacitors in series 1 1 1 1 C C1 C 2 C3 Time constant τ=RC Capacitor discharge Q = Qoe-t/ τ, I = Io e-t/ τ, V = Vo e-t/ τ Magnetic fields F Bqv Force on a wire F BIL sin Torque on a coil T = BIAn Magnetic flux linkage NΦ = NBAcosθ E.m.f. induced in a coil = E.m.f. induced in a moving conductor Φ Force on moving charge N t BLv Modern Physics E hf Photoelectric effect hf Φ E De Broglie Energy E = mc2 Exemplar k Photon energy max h mv © NCUK Ltd. 2021 Page 5 of 16 IFYPH003 Physics Mathematics sin (90 o – ) = cos ln (x n) = n ln x ln (e kx) = k x Equation of a straight line y = mx + c Surface area of a cylinder Surface area of a sphere =2rh+2r2 =4r2 Volume of a cylinder Volume of a sphere = r 2h = 4 r 3/ 3 For small angles sin tan cos 1 Exemplar © NCUK Ltd. 2021 (in radians) Page 6 of 16 IFYPH003 Physics Questions 1-13 Answer ALL questions. These questions carry 40 marks in total. Question 1 [1] When using the SI system, the units for velocity might be written as: i) mms-1 ii) m ms-1 iii) mm s-1 Select from the answers below which of these abbreviations for the units are correct. A B C D i) and ii) are correct ii) and iii) are correct i) and iii) are correct All three are correct Question 2 [1] A nuclide decays by β+ emission. State which of the following statements, A-D is correct: A B C D The atomic number of the nuclide will increase by 1 and an antineutrino will be emitted. The atomic number of the nuclide will decrease by 1 and an antineutrino will be emitted. The atomic number of the nuclide will increase by 1 and a neutrino will be emitted. The atomic number of the nuclide will decrease by 1 and a neutrino will be emitted. Question 3 [1] Photoelectrons are emitted from a metal surface when the energy of the incident photons is greater than the work function of the metal. State which of the following statements, A-D, is then correct: A B C D The maximum kinetic energy of the photoelectrons decreases when the intensity of the incident radiation is increased. The maximum kinetic energy of the photoelectrons decreases when the wavelength of the incident radiation is increased. The maximum kinetic energy of the photoelectrons increases when the wavelength of the incident radiation is increased. The maximum kinetic energy of the photoelectrons increases when the intensity of the incident radiation is increased. QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 7 of 16 IFYPH003 Physics Question 4 [1] State which of the following statements, A-D, is correct. A B C D Both transverse and longitudinal waves can be polarized. Electromagnetic waves travelling in free space all move at the same speed. The plane of the vibrations of an electromagnetic wave is parallel with the direction of travel. The plane of vibration of a longitudinal wave is perpendicular to the direction of travel Question 5 [1] State which of the following statements, A-D, is correct: A B C D The internal energy of a system is given by the total kinetic energy of the molecules in the system. Increasing the temperature of a body will lead to an increase in its internal energy. Thermal energy is transferred from a region of lower temperature to a region of higher temperature. Whilst a substance is changing state both its internal energy and its temperature will remain constant. Question 6 [1] An electron has a de Broglie wavelength of 1.27 x 10-10 m. Its kinetic energy in electron volts will be: A B C D 1.64 x 10-5 eV 3.27 x 10-5 eV 94.1 eV 188 eV Question 7 [1] A railway carriage of mass 4.50 x 104 kg, moving at 5.60 m s-1 collides with an initially stationary wagon of mass 7.20 x 103 kg. The carriage and wagon separate after the collision and the carriage moves at a speed of 4.40 m s-1 in the same direction as before the collision. The speed of the wagon after the collision will be A B C D 5.60 6.25 7.50 62.5 m m m m s-1 s-1 s-1 s-1 QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 8 of 16 IFYPH003 Physics Question 8 [1] A uniform brass wire of initial length 1.75 m is attached to a rigid support at its top end and hangs vertically downwards. It is stretched elastically by a force of 36.8 N and increases in length by 2.64 mm. Young’s modulus for brass = 1.00 x 1011 Pa The diameter of the wire must be: A B C D 5.57 2.79 3.11 1.56 x x x x 10-4 m 10-4 m 10-4 m 10-4 m Question 9 [1] A rectangular coil of wire measuring 30 mm x 20 mm and consisting of 50 turns is placed in a uniform magnetic field of 3.69 x 10-3 T. The torque on the coil when the plane of the coil is at an angle of 20° to the direction of the magnetic field and a current of 250 mA is flowing through the coil will be: A B C D 2.60 9.47 5.20 1.89 x x x x 10-5 10-6 10-7 10-7 N N N N m m m m Question 10 [1] An electron in the 5.70 eV excited state of a mercury atom falls to the 4.90 eV excited state of the atom. Determine the wavelength of the photon that will be emitted. A B C D 1.55 2.86 1.55 2.86 x x x x 10-7 10-7 10-6 10-6 m m m m QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 9 of 16 IFYPH003 Physics Question 11 (a) Determine the magnitude of the electric field strength at a distance of 50.0 mm from a small negatively charged, 20 μC point charge, placed in a vacuum. (b) Point charges of +2 μC, +5 μC, +7μC and -6 μC are placed at the corners of a square of side length 0.50 m. A point charge Q, of -4 μC is placed at the centre of the square. Assume ε = εo. [2] i. Determine the magnitude of the resultant force on charge Q. [6] ii. Determine the direction of the resultant force on charge Q. [2] Question 12 A narrow beam of purple light contains two colours, red light of wavelength 6.00 x 10-7 m and violet light of an unknown wavelength. The same light source is used in two separate experiments as described below. (a) (b) The narrow beam of purple light is incident normally on a plane diffraction grating. i. Determine the spacing between the lines on the grating if the 2nd order red line has a diffraction angle of 47°. [2] ii. The 3rd order violet line is also at this same diffraction angle. Determine the wavelength of the violet light. [2] iii. Determine the maximum diffraction order visible for the violet light. [2] The purple light is then used in a Young’s double slit experiment. The slit spacing is 0.25 mm and the distance between the fourth red fringe on one side of the centre to that of the fourth red fringe on the other side of the centre is 24.0 mm. i. Determine the distance between the double slits and the screen. [2] ii. Determine the spacing between the violet fringes. wavelength you obtained in part a)). [2] (Use the QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 10 of 16 IFYPH003 Physics Question 13 (a) Define electromotive force (e.m.f.) of a power supply. [2] (b) Cell A has an e.m.f. ε and internal resistance, r. It is connected in a circuit as shown below. With switch S open, a current of 0.250 A is recorded. With switch S closed, the current increases to 0.410 A. i. Determine the internal resistance, r, of the cell. [6] ii. Determine the e.m.f., ε, of the cell. [2] QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 11 of 16 IFYPH003 Physics Questions 14 - 18 Answer 3 questions ONLY These questions carry 60 marks in total. Question 14 (a) i. Define gravitational field strength. [2] ii. Assuming the Earth is a sphere of radius 6.37 x 103 km and that the acceleration due to gravity at the Earth’s surface is 9.81 m s-2, show that the mass of the Earth is 5.97 x 1024 kg. (You will need to use this value for the mass of the Earth in other parts of this question). [2] iii. Determine the average density of the Earth. [2] (b) The International Space Station (ISS) orbits the Earth at a height of 412 km above its surface. Determine the time taken in minutes for the ISS to complete one circular orbit of the Earth. (c) A communication satellite is in a synchronous orbit of the Earth. [5] i. What is the satellite’s period of rotation. [1] ii. Determine the satellite’s angular velocity. [2] iii. Determine the radius of the satellite’s orbit around the Earth. [3] iv. Determine the linear velocity of the satellite in km h-1. [3] QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 12 of 16 IFYPH003 Physics Question 15 Radium-223 (Ra-223) is an isotope used in the treatment of bone cancer. It decays by α-particle emission to radon-219 (Rn-219). (a) (b) Measurements of the activity of a sample of Ra-223 gave the following results: Time/days 0 5 10 15 20 25 30 Activity/ kBq 442 329 245 182 135 101 595 i. Plot a graph of activity (y axis) against time (x axis). [4] ii. Use the graph to determine the half life of Ra-223. [2] iii. Determine the decay constant of Ra-223. [2] iv. How could the results in the table be used to obtain a straight line graph? [2] v. Describe how the decay constant would be obtained from this straight line graph. Determine the energy, Q, in joules, released when an atom of Ra-223 undergoes α-decay. The atomic masses are as follows: Ra-223 223.0185u Rn-219 219.0095u α particle 4.0015u Use all of the significant figures shown in your calculations. [2] If all the energy released becomes the combined kinetic energy of the radon atom and α-particle, determine the recoil velocity of the radon atom. [4] i. ii. [4] QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 13 of 16 IFYPH003 Physics Question 16 A child is playing with a ball of mass 0.850 kg on a cliff top. The child kicks the ball and it leaves the ground at an angle of 15° above the horizontal, at a speed of 17.5 m s-1. Unfortunately, the ball goes over the cliff edge and straight into the calm sea, 30.3 m below the top of the cliff. Ignoring air resistance: (a) Determine the maximum height above the sea reached by the ball. [4] (b) Determine the time taken for the ball to reach its maximum height. [2] (c) Determine the time taken for the ball to reach the sea. [5] (d) What happens to the horizontal component of the ball’s velocity during this motion? Determine the horizontal distance travelled by the ball before it lands in the sea. [1] (f) Determine the vertical component of velocity of the ball as it enters the sea. [3] (g) Determine the total kinetic energy of the ball as it enters the sea. [3] (e) [2] QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 14 of 16 IFYPH003 Physics Question 17 (a) A block of ice of mass 0.850 kg at -5 °C is melted by a 2 kW heater and the resulting water continues to be heated. Determine the time taken, in minutes, to melt the ice and increase the water temperature to 35 °C, if the process is 75% efficient. Specific heat capacity of ice , cice = 2100 J kg-1 K-1 Specific heat capacity of water, cw = 4180 J kg-1 K-1 [4] Specific latent heat of fusion of ice, Li = 3.34 x 105 J kg-1 (b) (c) A cylinder of volume 3.00 x 10-3 m3 contains helium gas at a temperature of 200 K and a pressure of 4.35 x 104 Pa. i. Determine the number of moles of helium inside the cylinder. [2] ii. Determine the number of atoms of helium in the cylinder. [2] iii. The molar mass of helium is 4.00 x 10-3 kg. Determine the mass of 1 atom of helium. [2] iv. Determine the volume that the helium would occupy at s.t.p. (0 °C and 1.01 x 105 Pa). [3] v. Determine the density of helium at s.t.p. [3] A glass container, initially at a temperature of 20 °C is placed in liquid nitrogen. 0.250 kg of liquid nitrogen is boiled off in cooling down the glass to the liquid nitrogen temperature of -196 °C. i. Determine the mass of the glass container, ignoring all other sources of heat gain or loss. [2] Specific heat capacity of glass = 0.750 kJ kg-1 K-1 Specific latent heat of vaporisation of nitrogen = 209 kJ K-1 ii. Liquid helium at its boiling temperature of -269 °C is then poured into the glass container. Determine the mass of helium that will be boiled off when the container is cooled down to the temperature of the liquid helium, assuming all other sources of heat gain or loss are ignored. [2] Specific latent heat of vaporisation of helium = 25.0 kJ kg-1 QUESTIONS CONTINUE ON NEXT PAGE Exemplar © NCUK Ltd. 2021 Page 15 of 16 IFYPH003 Physics Question 18 (a) Define simple harmonic motion (SHM). [2] (b) The upper end of a vertical spring of original length 0.120 m is attached to a clamp stand. A mass of 0.250 kg is fastened to the lower end of the spring. The spring constant is 30.5 N m-1. i. Determine the stretched length of the spring. [3] ii. The mass is then pulled down a further 28.0 mm and released so that it vibrates with SHM. Determine the time period of this vibration. [2] iii. Determine the frequency of the vibration. [1] iv. Determine the magnitude of the acceleration of the mass at the instant it was released. [3] v. Determine the maximum kinetic energy of the mass. [3] vi. Sketch a graph to show how the kinetic energy of the mass (y axis) varies with time (x axis) over one full cycle of the vibration, starting with the mass at its lowest point. [2] vii. Determine the time taken for the mass to move directly from a position 15.0 mm below the equilibrium position to 15.0 mm above the equilibrium position. [4] - Exemplar This is the end of the examination. - © NCUK Ltd. 2021 Page 16 of 16