1. preparation
| s18 qp21 Q1(a) |
| State what is meant by a scalar quantity and by a vector quantity. |
| a scalar has magnitude (only) a vector has magnitude and direction |
| w19 qp22 Q1(a) |
| Distinguish between vector and scalar quantities. |
| scalar quantity has (only) magnitude vector quantity has magnitude and direction |
| s21 qp23 Q1(a)ii |
| State two properties that are possessed by both scalar and vector physical quantities. |
| magnitude unit |
| s18 qp23 Q1(a) |
| An analogue voltmeter is used to take measurements of a constant potential difference across a resistor. For these measurements, describe one example of (i) a systematic error (ii) a random error |
| zero error or wrongly calibrated scale reading scale from different angles or wrongly interpolating between scale readings/divisions |
| s16 qp23 Q2(a) |
| Describe the effects, one in each case, of systematic errors and random errors when using a micrometer screw gauge to take readings for the diameter of a wire. |
| Systematic error: the reading is always larger or smaller than (or varying from) the true reading by a constant amount Random error: scatter in readings about the true reading |
| s20 qp21 Q1(b)ii |
| Measurements of a constant current in a wire are taken using an analogue ammeter. For these measurements, describe one possible cause of: 1. a random error 2. a systematic error |
| reading scale from different angles or (wrongly) interpolating between scale readings/divisions zero error or wrongly calibrated scale |
| s16 qp23 Q2(b) |
| Distinguish between precision and accuracy when measuring the diameter of a wire. |
| precision: the size of the smallest division (on the measuring instrument) or 0.01 mm for the micrometer accuracy: how close (diameter) value is to the true (diameter) value |
| s17 qp21 Q1 (b)(i) 1 |
| Explain the difference between accuracy and precision. |
| accuracy is determined by the closeness of the value(s)/measurement(s) to the true value precision is determined by the range of the values/measurements |
| s17 qp22 Q1(c)(ii)1 |
| State what is meant by precision. |
| precision is determined by the range in the measurements/values/readings/data/results |
| s20 qp23 Q1(b) |
| This set of measurements has high precision, but low accuracy. Describe what is meant by (i) high precision (ii) low accuracy |
| the measurements have a small range the (average of the) measurements is not close to the true value |
2. kinematics
| m19 qp22 Q2(a)i |
| Define displacement |
| distance in a specified direction (from a point) |
| s20 qp23 Q1(a) |
| State one similarity and one difference between distance and displacement. |
| similarity: both have magnitude difference: distance is a scalar/does not have direction or displacement is a vector/has direction |
| s15 qp 21 Q2(a) |
| Define speed and velocity and use these definitions to explain why one of these quantities is a scalar and the other is a vector. |
| 1. speed = distance / time, speed is a scalar as distance has no direction 2. velocity = displacement / time, velocity is a vector as displacement has direction |
| m17 qp22 Q3(a) s17 qp22 Q2(a) s19 qp21 Q1(a) s20 qp22 Q1(a) s22 qp21 Q1(a) |
| Define velocity. |
| ver1 change of displacement / time (taken) ver2 rate of change of displacement \[ v = \frac{\vec{s}}{\Delta t} \] |
| s16 qp22 Q1(a) w19 qp22 Q2(a) s21 qp23 Q2(a) |
| Define acceleration. |
| acceleration = change in velocity / time (taken) or rate of change of velocity |
3. dynamics
| s18 qp22 Q1(a) m21 qp22 Q1(c)i |
| Define force. |
| rate of change of momentum |
| s18 qp21 Q3(a) |
| State what is meant by the mass of a body. |
| mass is the property (of a body/object) resisting changes in motion or mass is the quantity of matter (in a body) |
| s17 qp22 Q4(a) s18 qp21 Q2(a) s20 qp23 Q2(a) |
| State Newton’s first law of motion. |
| a body/mass/object continues (at rest or) at constant/uniform velocity unless acted on by a resultant force |
| s16 qp21 Q3(a)ii s17 qp23 Q2(a) w18 qp23 Q3(a) s19 qp22 Q2(a) s20 qp21 Q2(a) |
| State Newton’s second law of motion. |
| (resultant) force is proportional/equal to rate of change of momentum |
| w19 qp22 Q3(a) |
| State Newton’s third law of motion. |
| force on body A (by body B) is equal (in magnitude) to force on body B (by body A) force on body A (by body B) is opposite (in direction) to force on body B (by body A) |
| w15 qp22 Q4(a) w17 qp22 Q2(a) s21 qp23 Q3(a) |
| Define moment of a force (about a point). |
| ver1 product of the force and the perpendicular distance to/from a point/pivot Ver2 force × perpendicular distance (of line of action of force) to/from a point \[ \tau = F\times r_\perp \] |
| s20 qp23 Q3(a) |
| State the principle of moments. |
| for a body in (rotational) equilibrium sum/total of clockwise moments about a point = sum/total of anticlockwise moments about the (same) point |
| w16 qp22 Q3(a) s17 qp21 Q2(a) s20 qp22 Q3(a) s21 qp22 Q1(b) |
| State the two conditions for an object to be in equilibrium. |
| resultant force (in any direction) is zero. resultant moment/torque (about any point) is zero. |
| s19 qp23 Q3(a) s22 qp21 Q2(a) |
| State what is meant by the centre of gravity of a body. |
| the point where (all) the weight (of the body) is considered/taken to act |
4. momentum
| s19 qp22 Q2(a) |
| Define linear momentum. |
| (momentum =) mass × velocity \[ \vec{p} = m\times \vec{v} \] |
| s16 qp23 Q5(a) |
| State the law of conservation of momentum. |
| the total momentum of a system (of colliding particles) remains constant provided there is no resultant external force acting on the system/ isolated or closed system. |
| m17 qp22 Q2(a) w17 qp23 Q3(a) s18 qp22 Q2(a) |
| State the principle of conservation of momentum. |
| sum / total momentum of bodies is constant or sum / total momentum of bodies before = sum / total momentum of bodies after for an isolated / closed system / no (resultant) external force |
5. work, energy and power
| s15 qp 22 Q1(a) |
| Use the definition of work done to show the unit of work: |
| ver1 (work done)= force × displacement moved in the direction of the force unit = kg m2s-2 |
| m18 qp22 Q2(a)i s18 qp23 Q2(a) w19 qp23 Q2(a) s20 qp22 Q3(a) m21 qp22 Q2(a) |
| State what is meant by work done. |
| ver2 force × distance moved in the direction of the force |
| s15 qp23 Q3(a) w17 qp23 Q1(a)i s22 qp21 Q3(a)i |
| Define power. |
| ver1 (power =) work done / time (taken) or rate of work done ver 2 work (done) / time (taken) or energy (transferred) / time (taken) \[ P=\frac{W}{\Delta t} \] |
| s16 qp21 Q4(a) |
| State what is meant by elastic potential energy. |
| The energy stored in a body due to its extension/compression/deformation/change in shape/size. |
| s16 qp23 Q3(a) |
| Explain what is meant by gravitational potential energy and by kinetic energy. |
| gravitational potential energy: the energy/ability to do work of a mass that it has or is stored due to its position/height in a gravitational field kinetic energy: energy/ability to do work a object/body/mass has due to its speed/velocity/motion/movement |
| w18 qp22 Q2(a)ii w18 qp 23 Q2(a) |
| Explain what is meant by kinetic energy |
| energy (of a mass/body) due to motion / speed / velocity |
6. matter
| w16 qp21 Q1(a) s21 qp21 Q1(a) |
| Define density. |
| (density =) mass / volume \[ \rho = \frac{m}{V} \] |
| w16 qp22 Q1(a) s23 qp22 Q1 (a)i |
| Define pressure. |
| force/area (normal to the force) |
| s17 qp21 Q3(c)i s18 qp23 Q2(b)ii |
| Explain the origin of the upthrust. |
| pressure changes with depth (in water) or pressure on bottom (of cylinder) different from pressure on top pressure on bottom of cylinder greater than pressure on top or force (up) on bottom of cylinder greater than force (down) on top |
| w16 qp21 Q3(a) w16 qp23 Q3(a) |
| State Hooke’s law. |
| force/load is directly proportional to extension/compression provided proportionality limit is not exceeded |
| s17 qp23 Q4(c) |
| Describe how to determine whether the extension of the spring is elastic. |
| remove the force/masses and the spring returns to its original length if elastic |
| m18 qp22 Q3(a) |
| For the deformation of a wire under tension, define (i) stress (ii) strain |
| stress: force / (cross-sectional) area \[ \sigma = \frac{F}{A} \] strain: extension / original length \[ \epsilon = \frac{\Delta x}{l} \] |
| w17 qp21 Q4(a) |
| Define strain. |
| (strain =) extension / original length \[ \epsilon = \frac{\Delta x}{l} \] |
| s16 qp22 Q3(a) s18 qp23 Q4(a) |
| Define the Young modulus. |
| Young modulus = stress / strain or the ratio of stress to the strain of an object. |
7. DC circuits
| s16 qp21 Q6(a) w17 qp22 Q5(a) w18 qp23 Q6(a) |
| Define the coulomb. |
| (coulomb is) ampere second As |
| w17 qp22 Q6(a) |
| State what is meant by an electric current. |
| flow of charge carriers(electrons) |
| s18 qp21 Q6(a) s20 qp23 Q5(a) |
| Define the volt. |
| joule / coulomb \[ \mathrm{V}=\frac{\mathrm{J}}{\mathrm{C}} \] |
| s15 qp22 Q1(b) |
| Define potential difference. |
| (potential difference) = \frac{work (done) or energy (transformed) from electric to other forms}{charge} |
| w16 qp21 Q6(a) |
| Define electric potential difference (p.d.). |
| work done or energy (transform ed) (from electrical to other forms) per unit charge. |
| w15 qp22 Q6(a) s21 qp23 Q5(a) |
| Define electromotive force (e.m.f.) for a battery. Define the electromotive force (e.m.f.) of a source. |
| ver 1 energy converted from chemical to electrical per unit charge ver2 energy per unit charge energy transferred by source driving charge around the complete circuit or energy transferred from other forms to electrical energy |
| s17 qp22 Q7(a) |
| Define electromotive force (e.m.f.) of a cell. |
| energy transformed from chemical to electrical / unit charge (driven around a complete circuit) |
| m19 qp22 Q6(a) |
| Using energy transformations, describe the electromotive force (e.m.f.) of a battery and the potential difference (p.d.) across a resistor. |
| e.m.f.: energy transferred from chemical to electrical (per unit charge) p.d.: energy transferred from electrical to thermal (per unit charge) |
| s19 qp23 Q1(a) |
| Define resistance. |
| potential difference / current \[ R=\frac{V}{I} \] |
| s16 qp23 Q6(a) s17 qp21 Q6(a) w17 qp21 Q7(a) s19 qp23 Q6(a) s21 qp22 Q5(a) |
| Define the ohm. |
| ohm is volt per ampere or volt / ampere \[ \Omega = \frac{V}{A} \] |
| s18 qp22 Q6(a)i w18 qp23 Q7(a) w19 qp22 Q6(a) m21 qp22 Q6(a) s22 qp21 Q6(a) |
| State Kirchhoff’s first law. |
| sum of current(s) into junction = sum of current(s) out of junction or (algebraic) sum of current(s) at a junction is zero |
| w16 qp22 Q5(a) m18 qp22 Q5(a) s19 qp22 Q5(a) s21 qp21 Q5(a) |
| State Kirchhoff’s second law. |
| total/sum of electromotive forces or e.m.f.s = total/sum of potential differences or p.d.s around a loop/(closed) circuit |
| s17 qp23 Q6(a)i |
| Describe the I–V characteristic of a metallic conductor at constant temperature |
| straight line through the origin |
| s17 qp23 Q6(a)ii |
| Describe the I–V characteristic of a semiconductor diode. |
| zero current for one direction (–ve V) up to zero or a few tenths of volt (+ve V) straight line positive gradient/increasing gradient (+ve V) |
8. Waves
| s20 qp21 Q4(a)i |
| By reference to the direction of propagation of energy, state what is meant by a longitudinal wave. |
| vibrations (of particles) are parallel to direction of energy propagation |
| s19 qp22 Q4(a) |
| For a progressive water wave, state what is meant by: (i) displacement, (ii) amplitude. |
| distance (in a specified direction of particle/point on wave) from the equilibrium position the maximum distance (of particle/point on wave) from the equilibrium position or the maximum displacement (of particle/point on wave) |
| s18 qp21 Q4(a) s18 qp22 Q4(a)ii w19 qp22 Q4(5) s21 qp21 Q4(a) s21 qp22 Q4(a) |
| For a progressive wave, state what is meant by (i) the period, (ii) the wavelength. |
| time for one oscillation/one vibration/one cycle or time between adjacent wavefronts/points in phase or shortest time between two wavefronts/points in phase distance moved by wavefront/energy during one cycle/oscillation/period (of source) or minimum distance between two wavefronts or distance between two adjacent wavefronts or minimum distance between two points having the same displacement and moving in the same direction |
| w16 qp21 Q4(a) w16 qp23 Q4(a) s17 qp22 Q5(a) s23 qp23 Q4(a) |
| State what is meant by the frequency of a progressive wave. |
| the number of oscillations per unit time of the source/of a point on the wave/of a particle (in the medium) or the number of wavelengths/wavefronts per unit time passing a (fixed) point |
| s18 qp23 Q5(a) |
| State the relationship between the intensity and the amplitude of a wave. |
| intensity \propto (amplitude)2 \[ \mathrm{I} \propto \mathrm{A}^2 \] |
| s16 qp22 Q4(a) |
| By reference to the direction of the propagation of energy, state what is meant by a longitudinal wave and by a transverse wave. |
| longitudinal: vibrations/oscillations (of the particles/wave) are parallel to the direction or in the same direction (of the propagation of energy) transverse: vibrations/oscillations (of the particles/wave) are perpendicular to the direction (of the propagation of energy) |
| s17 qp21 Q4(a) w17 qp22 Q4(a) m18 qp22 Q4(a) m22 qp22 Q5(a)i |
| State the conditions required for the formation of stationary waves. |
| (two) waves travelling (at same speed) in opposite directions overlap/superpose waves (are same type and) have same frequency/wavelength |
| w15 qp23 Q6(a) |
| Explain how stationary waves are formed in the tube. |
| waves from loudspeaker (travel down tube and) are reflected at closed end two waves (travelling) in opposite directions with same frequency/wavelength overlap |
| w18 qp23 Q4(b)i s22 qp21 Q5(a) |
| Explain how the stationary wave is formed on the string. |
| wave (moves along string and) reflects at fixed point/Y/X/end/wall/boundary the incident and reflected waves interfere/superpose |
| s19 qp23 Q5(a) |
| Explain how the stationary wave is formed from the incident sound wave. |
| (incident) wave reflects at end/top of tube (incident) wave and reflected wave interfere/superpose |
| w17 qp21 Q3(b)i s18 qp22 Q4(a)i |
| State what is meant by an antinode of the stationary wave. |
| (position where) maximum amplitude occurs |
| s15 qp22 Q6(a) |
| State two differences between progressive waves and stationary waves. |
| 1. progressive waves transfer/propagate energy and stationary waves do not 2. amplitude constant for progressive wave and varies (from max/antinode to min/zero/node) for stationary wave |
| w15 qp21 Q5(a) |
| A progressive wave transfers energy. A stationary wave does not transfer energy. State two other differences between progressive waves and stationary waves. |
| 1. in terms of amplitude progressive: all particles have same amplitude stationary: no nodes or antinodes or maximum to minimum/zero amplitude 2. in terms of phase progressive: adjacent particles are not in phase stationary: waves particles are in phase (between adjacent nodes) |
| w17 qp21 Q3(a) s20 qp22 Q4(a) |
| State the difference between a stationary wave and a progressive wave in terms of i) the energy transfer along the wave, ii) the phase of two adjacent vibrating particles. |
| in a stationary wave energy is NOT transferred, while in a progressive wave energy is transferred in a stationary wave (adjacent) particles are in phase, while in a progressive wave (adjacent) particles are out of phase/have a phase difference/not in phase |
| s15 qp22 Q6(a) |
| State what is meant by diffraction and by interference. |
| diffraction is the spreading of a wave as it passes through a slit or past an edge when two (or more) waves superpose/meet/overlap resultant displacement is the sum of the displacement of each wave |
| s18 qp21 Q5(a) s19 qp21 Q5(c)i |
| Explain what is meant by (i) diffracted waves (ii) coherent waves |
| waves spread at (each) slit/gap constant phase difference (between (each of) the waves) |
| w16 qp21 Q5(a) w16 qp22 Q4(a) |
| State what is meant by the diffraction of a wave. |
| wave incident on/passes by or through an aperture/edge wave spreads (into geometrical shadow) |
| m19 qp22 Q5(a) s20 qp21 Q4(a)i m21 qp22 Q4(a) s21 qp22 Q4(b) s21 qp23 Q4(a) |
| State the principle of superposition. |
| ver 1 (two) waves meet/overlap (at a point) (resultant) displacement is sum of the displacement of each wave ver2 (when two or more) waves meet/overlap (at a point) (resultant) displacement is sum of the individual displacements |
| s16 qp22 Q5(a) |
| Light of a single wavelength is incident on a diffraction grating. Explain the part played by diffraction and interference in the production of the first order maximum by the diffraction grating. |
| diffraction: spreading/diverging of waves/light (takes place) at (each) slit/ element/gap/aperture interference: overlapping of waves (from coherent sources at each element) when path difference exactly equals λ/phase difference of 360°/2π (to produces the first order) |
| s17 qp22 Q6(a)i |
| Explain the part played by diffraction in the production of the fringes, |
| waves at (each) slit/aperture spread (into the geometric shadow) wave(s) overlap/superpose/sum/meet/intersect |
| s17 qp23 Q5(a) |
| Describe the diffraction of light at a diffraction grating. |
| waves at the elements/slits waves spread (into the geometric shadow) |
| s17 qp22 Q6(a)ii |
| Explain the reason why a double slit is used rather than two separate sources of light. |
| there is not a constant phase difference/coherence (for two separate light source(s)) or waves/light from the double slit are coherent/have a constant phase difference |
| s15 qp21 Q6 (a)i w19 qp23 Q5(a) |
| Explain the meaning of coherence and interference. |
| coherent: constant phase difference interference: the (overlapping of waves and the) sum of/addition of displacement of two waves ver 2 (interference is) the sum/addition/combination of the displacements of overlapping/meeting waves |
| s16 qp22 Q4(c)i m17 qp22 Q4(a) s17 qp21 Q5(a) |
| Describe the Doppler effect. |
| ver1 change/difference in the observed/apparent frequency when the source is moving (relative to the observer) ver2 change in observed/apparent frequency when source moves relative to observer ver3 observed frequency is different to source frequency when source moves relative to observer |
9. Particles
| s16 qp22 Q7(a) |
| Electric current is a flow of charge carriers. The charge on the carriers is quantised. Explain what is meant by quantised. |
| charge exists only in discrete amounts |
| s16 qp23 Q8(a) |
| Distinguish between an α-particle and a β+-particle. |
| α-particle is 2 protons and 2 neutrons; β+-particle is positive electron/positron α-particle has charge +2e; β+-particle has +e charge α-particle has mass 4u; β+-particle has mass (1/2000)u α-particle made up of hadrons; β+-particle a lepton |
| s15 qp23 Q7 (a)i |
| Explain the meaning of spontaneous radioactive decay. |
| (rate of decay) not affected by any external factors or changes in temperature and pressure etc. |
| w15 qp22 Q8(a) w16 qp21 Q7(c) s19 qp21 Q7(a) m21 qp22 Q7(a) s21 qp22 Q6(a) s21 qp23 Q6(b) |
| The results of the α-particle scattering experiment gave evidence for the structure of the atom. State two results and the associated conclusions. |
| Result: majority / most (of the α-particles) went straight through/were deviated by small angles Conclusion: most of the atom is (empty) space or size/volume of nucleus very small compared with atom Result: a small proportion were deflected through large angles or >90° or came straight back Conclusion: the mass or majority of mass is in a (very) small charged volume/region/nucleus |
| s17 qp22 Q8(a) |
| Describe two differences between the decay of a nucleus that emits a β–particle and the decay of a nucleus that emits a β+ particle. |
| neutron changes to proton + β– particle (electron) proton changes to neutron + β+ particle (positron) (electron) antineutrino also emitted (electron) neutrino also emitted |
| w16 qp21 Q1(a) |
| State one difference between a hadron and a lepton. |
| hadron not a fundamental particle/lepton is fundamental particle or hadron made of quarks/lepton not made of quarks or strong force/interaction acts on hadrons/does not act on leptons |
10. Electric field
| w19 qp23 Q3(a) |
| State the property of an object that experiences a force when the object is placed in (i) gravitatitonal field (ii) electric field |
| mass charge |
| s19 qp22 Q6(a) |
| State what is meant by a field line (line of force) in an electric field. |
| path/direction in which a (free) positive charge will move |
| s17 qp23 Q7(a) w17 qp21 Q6(a) w17 qp23 Q5(a) m19 qp22 Q4(a) |
| Define electric field strength. |
| force per unit (positive) charge \[ \vec{E} =\frac{\vec{F}}{q} \] |
| w19 qp21 Q6(a) |
| Define electric potential difference (p.d.). |
| work done / charge or energy (transferred from electrical to other forms) / charge |
