Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Velocity changes from 3 to 15 metres per second in 6 s. Find acceleration. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A negative velocity always means the object is slowing down. This claim is false: Negative velocity indicates direction under the chosen sign convention; it does not necessarily mean slowing down.
Key:
Motion graphs and acceleration: The gradient of a displacement-time graph is velocity. The area under a velocity-time graph gives displacement. A constant-acceleration formula is valid only when its assumption is justified.
| English | 中文 | 拼音 |
|---|---|---|
| velocity/vəˈlɒsɪti/ | 速度 | sù dù |
| acceleration/əkˌseləˈreɪʃn/ | 加速度 | jiā sù dù |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A 2 kg trolley travels at 3 metres per second. Find its momentum. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
An object moving at constant velocity must have a nonzero resultant force. This claim is false: Balanced forces do not require the object to be at rest. Mass and weight have different units and meanings.
Key:
Forces, momentum and safe stopping: Impulse equals momentum change. Increasing stopping time for the same momentum change reduces average force. Identify external forces before applying momentum conservation.
| English | 中文 | 拼音 |
|---|---|---|
| momentum/məʊˈmentəm/ | 动量 | dòng liàng |
| resultant force/rɪˈzʌltənt fɔːs/ | 合力 | hé lì |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A device receives 250 J and gives 150 J useful output. Find efficiency as a percentage. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Dissipated energy is destroyed. This claim is false: Efficiency cannot exceed 100% for a properly defined energy balance. Energy dissipated by heating is still conserved.
Key:
Energy stores, work and efficiency: Define the system and useful output before calculating efficiency. Doubling speed quadruples kinetic energy at constant mass. Power describes transfer per time, not total energy.
| English | 中文 | 拼音 |
|---|---|---|
| power/ˈpaʊə/ | 功率 | gōng lǜ |
| efficiency/ɪˈfɪʃənsi/ | 效率 | xiào lǜ |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A 12 N force acts perpendicularly 0.25 m from the pivot. Find torque. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Moment of inertia depends only on total mass, never its distribution. This claim is false: Torque has unit N m but is a turning effect, not an energy store. Moment of inertia changes if the same mass moves farther from the axis.
Key:
Rigid bodies and rotational dynamics: For a rigid body about a fixed axis, net torque equals moment of inertia multiplied by angular acceleration. Rotational kinetic energy depends on angular speed squared. Angular momentum is conserved when net external torque is zero.
| English | 中文 | 拼音 |
|---|---|---|
| torque/tɔːk/ | 力矩 | lì jǔ |
| moment of inertia/ˈməʊmənt ɒv ɪˈnɜːʃə/ | 转动惯量 | zhuǎn dòng guàn liàng |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A proper interval is 8 microseconds and gamma is 1.25. Find the other-frame interval. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
All inertial observers must measure the same time interval between any two events. This claim is false: Time dilation is not an instrument fault. Proper length is measured in the object rest frame; a contracted length is measured in a frame where it moves.
Key:
Relativity and measuring events: The Lorentz factor is 1 divided by the square root of 1 minus speed squared over light speed squared. Galilean velocity addition is an approximation for speeds much smaller than light speed.
| English | 中文 | 拼音 |
|---|---|---|
| proper time/ˈprɒpə taɪm/ | 固有时间 | gù yǒu shí jiān |
| inertial frame/ɪˈnɜːʃl freɪm/ | 惯性参考系 | guàn xìng cān kǎo xì |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A 2 kg sample with c=500 J per kilogram per degree warms by 3 °C. Find energy gain. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A temperature plateau always means zero energy transfer. This claim is false: A flat section of a heating curve can show a phase change, not absence of energy transfer. Do not substitute temperature for a temperature difference in E = mcΔT.
Key:
Thermal measurements and particle models: Temperature relates to particle motion in a model; internal energy includes kinetic and potential contributions. During a change of state, energy can change particle arrangements rather than temperature.
| English | 中文 | 拼音 |
|---|---|---|
| specific heat capacity/spəˈsɪfɪk hiːt kəˈpæsɪti/ | 比热容 | bǐ rè róng |
| latent heat/ˈleɪtənt hiːt/ | 潜热 | qián rè |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Incoming energy is 240 units and reflected energy 72. Find reflected percentage. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
One local weather observation establishes a global climate trend. This claim is false: The greenhouse effect is not the same process as ozone depletion. A carbon footprint estimate depends on its system boundary.
Key:
Climate evidence, energy budgets and policy: Distinguish mitigation, which addresses drivers, from adaptation, which reduces harm from impacts. A policy assessment needs evidence about effectiveness, cost, equity and uncertainty; one criterion is not the entire decision.
| English | 中文 | 拼音 |
|---|---|---|
| mitigation/ˌmɪtɪˈɡeɪʃn/ | 减缓 | jiǎn huǎn |
| adaptation/ˌædæpˈteɪʃn/ | 适应 | shì yìng |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
At fixed volume, pressure is 120 kPa at 300 K. Find pressure at 350 K. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A gas pressure ratio can always use Celsius temperatures. This claim is false: An ideal gas is a model with conditions of validity. Celsius zero is not zero molecular motion, and internal energy is not determined by pressure alone.
Key:
Gas models and absolute temperature: At fixed amount and volume, pressure is proportional to kelvin temperature. At fixed temperature and amount, pressure is inversely proportional to volume. State which quantities are fixed before choosing a relationship.
| English | 中文 | 拼音 |
|---|---|---|
| absolute temperature/ˈæbsəluːt ˈtemprɪtʃə/ | 绝对温度 | jué duì wēn dù |
| ideal gas/aɪˈdɪəl ɡæs/ | 理想气体 | lǐ xiǎng qì tǐ |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A gas gains 500 J of heat and does 200 J work. Find internal-energy change. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Every adiabatic process has constant temperature. This claim is false: Adiabatic does not mean constant temperature. Use the stated sign convention; some courses write work done on the gas with the opposite sign.
Key:
Thermodynamic systems and energy accounts: State a sign convention before using the first law. Here change in internal energy equals heat into the system minus work done by the system. Expansion work can reduce internal energy when no heat enters.
| English | 中文 | 拼音 |
|---|---|---|
| internal energy/ɪnˈtɜːnl ˈenədʒi/ | 内能 | nèi néng |
| adiabatic/ˌædiəˈbætɪk/ | 绝热的 | jué rè de |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A component has 12 V across it and carries 0.40 A. Find resistance. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A lamp uses up electric current as charge passes through it. This claim is false: Current is not used up by a lamp. A filament heats up, so its resistance need not remain constant as voltage changes.
Key:
Current, potential difference and resistance: Current is the same through components in series. Potential differences add around the series path. In parallel, branches share the same potential difference, while branch currents sum at a junction.
| English | 中文 | 拼音 |
|---|---|---|
| current/ˈkʌrənt/ | 电流 | diàn liú |
| potential difference/pəˈtenʃl ˈdɪfrəns/ | 电势差 | diàn shì chā |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
30 cycles take 45 s. Find period. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Every periodic motion satisfies the condition for simple harmonic motion. This claim is false: Not every repeated motion is SHM. A force proportional to displacement but directed away from equilibrium does not produce SHM.
Key:
Oscillation, resonance and phase: Velocity is greatest near equilibrium for ideal SHM, while acceleration magnitude is greatest at extreme displacement. Resonance can occur near the natural frequency under periodic driving, with amplitude limited by damping.
| English | 中文 | 拼音 |
|---|---|---|
| damping/ˈdæmpɪŋ/ | 阻尼 | zǔ ní |
| resonance/ˈrezənəns/ | 共振 | gòng zhèn |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Frequency is 8 Hz and wavelength is 0.25 m. Find wave speed. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Wave frequency always changes when a wave enters a new medium. This claim is false: The wave frequency does not change simply because the medium changes. A longitudinal wave has oscillations parallel to propagation.
Key:
Waves, measurement and refraction: At a boundary, frequency stays fixed by the source. A change of speed changes wavelength. Refraction follows from speed differences; angles are measured from the normal.
| English | 中文 | 拼音 |
|---|---|---|
| frequency/ˈfriːkwənsi/ | 频率 | pín lǜ |
| wavelength/ˈweɪvleŋθ/ | 波长 | bō cháng |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A 600 nm rest line is observed at 601.2 nm. Find z=(observed−rest)/rest. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
An observed redshift means light speed increased. This claim is false: The approximate shift relation does not show that light travels faster from an approaching source. A single unidentified line cannot safely establish a redshift.
Key:
Spectral shifts: a low-speed astronomical estimate: Compare a identified line with its laboratory rest wavelength. Use z = (observed−rest)/rest, then v approximately cz in the stated low-speed model. Do not apply this approximation without checking the regime or treating a cosmological redshift as a simple exact velocity.
| English | 中文 | 拼音 |
|---|---|---|
| redshift/ˈredʃɪft/ | 红移 | hóng yí |
| rest wavelength/rest ˈweɪvleŋθ/ | 静止波长 | jìng zhǐ bō cháng |
Example:
A 600 Hz source approaches a stationary observer at 20 m/s. Use v = 340 m/s. Find observed frequency. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
The Doppler effect always means the wave speed in the medium changed. This claim is false: A stationary source and moving observer require the observer-motion relation. Do not use the same denominator formula for every arrangement or import a sound formula into relativity.
Key:
Doppler effect: separate source motion from wave speed: For a source approaching a stationary observer along the line of sight, f observed = f source × v/(v−v source). Recession uses v+v source in the denominator. These are sound-wave models; light requires its appropriate relation.
| English | 中文 | 拼音 |
|---|---|---|
| Doppler shift/ˈdɒplə ʃɪft/ | 多普勒频移 | duō pǔ lēi pín yí |
| wavefront/ˈweɪvfrʌnt/ | 波面 | bō miàn |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Field strength is 18 units at r. Find it at 3r for an inverse-square field. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Gravity is zero everywhere a spacecraft experiences apparent weightlessness. This claim is false: Weightlessness in an orbiting spacecraft means apparent weight is small in free fall, not that there is no gravitational field.
Key:
Gravitational fields and orbital motion: For a point mass or outside a spherical mass, field strength follows an inverse-square distance dependence. Use distance from the centre, not height above the surface alone.
| English | 中文 | 拼音 |
|---|---|---|
| gravitational field/ˌɡrævɪˈteɪʃənl fiːld/ | 引力场 | yǐn lì chǎng |
| centripetal force/senˈtrɪpɪtl fɔːs/ | 向心力 | xiàng xīn lì |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Use E = V/d. Find E for 100 V across 0.025 m. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Every charged particle experiences a force along the electric field direction. This claim is false: Field strength is a vector. Potential difference is energy per charge and is not the same quantity. A field-line drawing is a model, not a set of physical threads.
Key:
Electric fields: force and a positive test charge: In a uniform field between ideal parallel plates, E = V/d away from edge effects. The force is F = qE, so its direction reverses for a negative charge. Coulomb force between ideal point charges decreases with separation squared.
| English | 中文 | 拼音 |
|---|---|---|
| test charge/test tʃɑːdʒ/ | 试探电荷 | shì tàn diàn hè |
| electric field strength/ɪˈlektrɪk fiːld streŋθ/ | 电场强度 | diàn chǎng qiáng dù |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Use r = mv/(|q|B). For m=2×10⁻²⁷ kg, v=2×10⁶ m/s, |q|=1×10⁻¹⁹ C and B=0.20 T, find r. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A magnetic force alone continuously increases the kinetic energy of a charged particle. This claim is false: A magnetic force can change momentum direction without doing work. Adding an electric field can change the energy, so conclusions about a magnetic field alone do not cover every combined-field apparatus.
Key:
Magnetic forces: turn velocity without increasing speed: Equate magnetic force with mv²/r to obtain r = mv/(|q|B) for perpendicular motion. A stronger field makes a smaller radius at fixed momentum. Parallel entry gives zero magnetic force in this model.
| English | 中文 | 拼音 |
|---|---|---|
| magnetic force/mæɡˈnetɪk fɔːs/ | 磁力 | cí lì |
| momentum/məʊˈmentəm/ | 动量 | dòng liàng |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
An ideal transformer has Np=400, Ns=100 and Vp=20 V. Find Vs. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A steady DC input produces continuous ideal transformer action. This claim is false: A transformer needs changing magnetic flux; a steady DC input does not provide continuous transformer action. Magnetic field direction is not automatically the direction of force.
Key:
Fields, motors and induction: Changing field strength, coil area, orientation or relative motion can change flux linkage. Lenz law describes an induced effect opposing the change producing it, consistent with energy conservation.
| English | 中文 | 拼音 |
|---|---|---|
| induction/ɪnˈdʌkʃn/ | 电磁感应 | diàn cí gǎn yìng |
| transformer/trænsˈfɔːmə/ | 变压器 | biàn yā qì |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Levels are −7.0 and −2.0 eV. Find the energy emitted in the downward transition. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A negative bound-state energy means an emitted photon has negative energy. This claim is false: Negative bound-state energies are relative to a chosen zero; they do not mean a negative photon energy is emitted. A larger downward energy difference gives higher frequency.
Key:
Atomic models and line spectra: An emitted photon corresponds to a transition to a lower energy level. Absorption requires a compatible energy difference. Rutherford scattering supported a small dense nucleus, but that experiment alone did not establish the complete quantum model.
| English | 中文 | 拼音 |
|---|---|---|
| energy level/ˈenədʒi ˈlevl/ | 能级 | néng jí |
| emission spectrum/ɪˈmɪʃn ˈspektrəm/ | 发射光谱 | fā shè guāng pǔ |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
Photon energy is 4.8 eV and work function 2.1 eV. Find maximum kinetic energy. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Doubling light intensity doubles each photon energy at fixed frequency. This claim is false: Electrons do not accumulate many sub-threshold photons in the elementary single-photon model. Do not confuse photon number with photon energy.
Key:
Photons and the photoelectric effect: Use photon energy = Planck constant × frequency. Maximum kinetic energy = photon energy - work function. Increasing intensity at fixed frequency increases photon arrival rate, not individual photon energy.
| English | 中文 | 拼音 |
|---|---|---|
| photon/ˈfəʊtɒn/ | 光子 | guāng zi |
| work function/wɜːk ˈfʌŋkʃn/ | 逸出功 | yì chū gōng |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
An initial source count is 160 per minute. Find it after three half-lives. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Half-life predicts the exact decay time of an individual nucleus. This claim is false: An irradiated object is not automatically radioactive. A half-life does not predict the exact decay time of one nucleus.
Key:
Nuclear changes and radiation evidence: Subtract background counts measured over the same time interval. Distinguish irradiation from contamination. Shielding, distance and reduced exposure time can reduce risk under a school-controlled procedure.
| English | 中文 | 拼音 |
|---|---|---|
| half-life/hɑːf laɪf/ | 半衰期 | bàn shuāi qī |
| background radiation/ˈbækɡraʊnd ˌreɪdɪˈeɪʃn/ | 本底辐射 | běn dǐ fú shè |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A U-235 nucleus plus one neutron produces fragments with mass numbers 141 and 92. How many neutrons balance the equation? Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
A balanced nucleon-number equation alone gives the energy release in joules. This claim is false: Mass number is not a precise mass in kilograms. Balanced integer labels alone do not calculate the released energy. Radioactive decay and neutron-induced fission are not interchangeable descriptions.
Key:
Fission: conserve charge and nucleons, account for energy: Separate conservation of nucleon number from conservation of total energy. Released neutrons may initiate further fissions, escape or be absorbed. A controlled reactor and an uncontrolled chain reaction have different neutron-management conditions.
| English | 中文 | 拼音 |
|---|---|---|
| chain reaction/tʃeɪn rɪˈækʃn/ | 链式反应 | liàn shì fǎn yìng |
| fission/ˈfɪʃn/ | 核裂变 | hé liè biàn |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A source gives flux 18 units. Find flux at three times the distance. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Apparent brightness alone always determines a star luminosity. This claim is false: The Sun is not expected to become a supernova. Redshift can support cosmological expansion; it does not mean every nearby object must move away from every observer.
Key:
Stars, radiation and scale: For isotropic emission without absorption, flux follows an inverse-square relationship with distance. Observed brightness alone therefore cannot establish luminosity.
| English | 中文 | 拼音 |
|---|---|---|
| flux/flʌks/ | 通量 | tōng liàng |
| luminosity/ˌluːmɪˈnɒsɪti/ | 光度 | guāng dù |
Supported HL focus. First assessment 2025; full Physics guide acquired (84 PDF pages). Remaining guide, assessment and practical requirements retain their recorded holds.
Prerequisites: read the stated quantities and units, use arithmetic and the model conditions below. Each lesson develops its own method before independent transfer.
These are original or explicitly fictional teaching examples, not actual measurements or completed assessed learner investigations.
Example:
A 40 cm reading has an absolute uncertainty of 1 cm. Find percentage uncertainty. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
Warn:
Repeating a measurement always removes a calibration offset. This claim is false: Repeating readings reduces random uncertainty in a mean but does not automatically remove a zero error. Do not quote more decimal places than your measurement can support.
Key:
Uncertainty, gradients and model testing: For a product or quotient, adding fractional uncertainties is a common maximum-uncertainty approximation. For a difference, add absolute uncertainties. A nonzero intercept can reveal an offset or an incomplete model.
| English | 中文 | 拼音 |
|---|---|---|
| systematic error/ˌsɪstəˈmætɪk ˈerə/ | 系统误差 | xì tǒng wù chā |
| uncertainty/ʌnˈsɜːtənti/ | 不确定度 | bù què dìng dù |
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