Specification H556. Explore a topic, practise the skill, and see where to focus next.
Try three questions →Explore the topic map ↓
OCR · Physics A · H556LearningP is independent of OCR · Physics A. Use the current official documents for assessment requirements.
Try three different Physics skills from this OCR · Physics A route. See what went right, understand a mistake, and find a useful next step.
A small preview of how LearningP turns answers into a clearer learning picture for students and parents.
OCR scientific convention labels the physical quantity followed by a slash and its unit. Potential difference V is measured in volts, so the heading is V / V.
Measure L with a metre rule and diameter d with a micrometer at several positions. Measure V and I, calculate R = V/I and A = πd²/4, then ρ = RA/L. Each quantity required by the model is measured.
Displacement is area under the v–t graph: s = ∫₀² 3t² dt = [t³]₀² = 8.0 m.
These tiles show your answers to three questions. They are a starting point, not a mastery score or grade prediction.
Correct answer: V / V
OCR scientific convention labels the physical quantity followed by a slash and its unit. Potential difference V is measured in volts, so the heading is V / V.
Correct answer: Wire length and diameter, plus current and p.d. so that R = V/I and ρ = RA/L
Measure L with a metre rule and diameter d with a micrometer at several positions. Measure V and I, calculate R = V/I and A = πd²/4, then ρ = RA/L. Each quantity required by the model is measured.
Correct answer: 8.0 m
Displacement is area under the v–t graph: s = ∫₀² 3t² dt = [t³]₀² = 8.0 m.
For parents: look at the explanation together. A correct answer is encouraging; a missed answer gives you something specific to work on. Broader practice over time is needed to understand progress.
Human reaction time is a large fraction of one period. Timing N oscillations makes the measured interval about N times larger while the start/stop uncertainty is similar; T = total time/N therefore has a smaller percentage uncertainty.
Watch for: Do not substitute numbers before stating the relationship used for Planning. Convert units first and explain what the calculated result means.
Current through the resistor must also pass through the ammeter, so the two are connected in series. An ammeter has low resistance and must not be placed directly across a supply.
Watch for: Do not substitute numbers before stating the relationship used for Implementing. Convert units first and explain what the calculated result means.
The best-fit line estimates the relationship. An acceptable worst line constrained by uncertainty bars gives a limiting gradient; comparing its gradient with the best gradient estimates gradient uncertainty.
Watch for: Do not substitute numbers before stating the relationship used for Analysis. Convert units first and explain what the calculated result means.
An anomalous value should be investigated rather than automatically removed. A repeat can show whether a recording or transient error occurred; any exclusion must be transparent and justified.
Watch for: Do not substitute numbers before stating the relationship used for Evaluation. Convert units first and explain what the calculated result means.
Software is a tool, not evidence of correctness. Checking formula references and hand-calculating sample rows can expose copied-cell, unit or logarithm errors before the gradient is interpreted.
Watch for: Do not substitute numbers before stating the relationship used for Practical skills. Convert units first and explain what the calculated result means.
Keeping lamp type and supply potential difference constant isolates circuit arrangement as the independent variable. Changing several factors together would make the cause of a brightness difference unclear.
Watch for: Do not substitute numbers before stating the relationship used for Use of apparatus and techniques. Convert units first and explain what the calculated result means.
A physical quantity is specified by a numerical value together with a unit. The number 4.7 alone does not identify the scale or kind of measurement.
Watch for: Do not substitute numbers before stating the relationship used for Physical quantities. Convert units first and explain what the calculated result means.
For s = ut + ½at²: ut has (m s⁻¹)(s) = m and at² has (m s⁻²)(s²) = m, matching s. Each distractor equates quantities with different base dimensions.
Watch for: Do not substitute numbers before stating the relationship used for S.I. units. Convert units first and explain what the calculated result means.
A small spread indicates precision, whereas closeness to the accepted value indicates accuracy. These readings have the first property but not the second.
Watch for: Do not substitute numbers before stating the relationship used for Measurements and uncertainties. Convert units first and explain what the calculated result means.
Displacement and velocity have both magnitude and direction, so they are vectors. Distance, speed, time and mass are scalar quantities.
Watch for: Do not substitute numbers before stating the relationship used for Scalars and vectors. Convert units first and explain what the calculated result means.
A horizontal line means distance does not change as time passes, so the object is stationary.
Watch for: Do not substitute numbers before stating the relationship used for Kinematics. Convert units first and explain what the calculated result means.
Reaction time varies naturally, but an outlier may reflect anticipation, distraction or measurement error. Repeats improve reliability; a justified treatment of anomalies produces a more representative mean.
Watch for: Do not substitute numbers before stating the relationship used for Linear motion. Convert units first and explain what the calculated result means.
Both have the same initial vertical velocity, vertical acceleration and vertical displacement. Horizontal motion does not affect their common fall time.
Watch for: Do not substitute numbers before stating the relationship used for Projectile motion. Convert units first and explain what the calculated result means.
Newton's second law gives a = F/m. With constant total mass, acceleration is directly proportional to resultant force. Repeats and a force–acceleration graph test this relationship.
Watch for: Do not substitute numbers before stating the relationship used for Dynamics. Convert units first and explain what the calculated result means.
At release, drag is zero or small. Weight minus upthrust produces acceleration. As speed rises, drag rises until drag + upthrust = weight; resultant force and acceleration are then zero.
Watch for: Do not substitute numbers before stating the relationship used for Motion with non-uniform acceleration. Convert units first and explain what the calculated result means.
Moment = force × perpendicular distance from the pivot. Increasing the lever arm increases turning effect for the same force; gears similarly transmit rotational effects.
Watch for: Do not substitute numbers before stating the relationship used for Equilibrium. Convert units first and explain what the calculated result means.
The ship's large hollow volume lowers average density. It sinks only until displaced water weighs as much as the ship, so upthrust balances weight.
Watch for: Do not substitute numbers before stating the relationship used for Density and pressure. Convert units first and explain what the calculated result means.
Energy from the battery's chemical store is transferred electrically to the motor and mechanically into the mass's gravitational store, with some thermal loss.
Watch for: Do not substitute numbers before stating the relationship used for Work and conservation of energy. Convert units first and explain what the calculated result means.
Kinetic energy is ½mv², so doubling speed multiplies the squared speed and therefore kinetic energy by four. This strongly affects energy dissipated in a collision.
Watch for: Do not substitute numbers before stating the relationship used for Kinetic and potential energies. Convert units first and explain what the calculated result means.
Efficiency is useful energy output divided by total energy input, or useful power output divided by total power input; multiply by 100 for a percentage.
Watch for: Do not substitute numbers before stating the relationship used for Power. Convert units first and explain what the calculated result means.
Loading and unloading measurements reveal whether extension is reversible. Different paths show hysteresis, and a non-zero final extension indicates permanent deformation.
Watch for: Do not substitute numbers before stating the relationship used for Springs. Convert units first and explain what the calculated result means.
A permanent extension after unloading is plastic deformation and indicates that the spring was taken beyond its elastic behaviour. Loading and unloading data reveal this hysteresis or permanent change.
Watch for: Do not substitute numbers before stating the relationship used for Mechanical properties of matter. Convert units first and explain what the calculated result means.
The swimmer exerts a backward force on the water, and the water exerts an equal forward force on the swimmer. The pair acts on different objects and is the same interaction.
Watch for: Do not substitute numbers before stating the relationship used for Newton's laws of motion. Convert units first and explain what the calculated result means.
For an isolated collision, momentum is conserved in both types. A perfectly elastic collision also conserves total kinetic energy; an inelastic collision transfers some kinetic energy to other forms.
Watch for: Do not substitute numbers before stating the relationship used for Collisions. Convert units first and explain what the calculated result means.
Conventional current is defined as the direction positive charge would move. Mobile electrons are negative, so their mean drift is opposite to conventional current.
Watch for: Do not substitute numbers before stating the relationship used for Charge. Convert units first and explain what the calculated result means.
Conduction electrons move rapidly in random directions. An applied field slightly biases this motion, producing a small mean drift velocity while the random components average to zero.
Watch for: Do not substitute numbers before stating the relationship used for Mean drift velocity. Convert units first and explain what the calculated result means.
A variable resistor is drawn as the resistor symbol with a diagonal arrow. Standard symbols make circuit diagrams unambiguous and should be connected with straight wires.
Watch for: Do not substitute numbers before stating the relationship used for Circuit symbols. Convert units first and explain what the calculated result means.
Both use volts, but their roles differ: a source raises the energy of charge, while a component transfers electrical energy to other forms.
Watch for: Do not substitute numbers before stating the relationship used for E.m.f. and p.d. Convert units first and explain what the calculated result means.
Adding a parallel branch increases total conductance. Both branches have the same potential difference and junction currents add, so total current is greater and R = V/I is below either branch resistance.
Watch for: Do not substitute numbers before stating the relationship used for Resistance. Convert units first and explain what the calculated result means.
In a metal, stronger lattice vibrations increase electron scattering, raising resistivity. In a semiconductor, temperature creates many more mobile carriers, so resistivity falls.
Watch for: Do not substitute numbers before stating the relationship used for Resistivity. Convert units first and explain what the calculated result means.
P = I²R = (3.0)² × 12 = 108 W. Equivalently V = IR = 36 V and P = VI = 108 W.
Watch for: Do not substitute numbers before stating the relationship used for Power. Convert units first and explain what the calculated result means.
There is only one route for charge in a series circuit, so charge conservation requires the same current through every component in that loop.
Watch for: Do not substitute numbers before stating the relationship used for Series and parallel circuits. Convert units first and explain what the calculated result means.
Chemical and conducting processes inside a real source oppose current and transfer some energy thermally. This is modelled by an internal resistance r in series with the ideal e.m.f.
Watch for: Do not substitute numbers before stating the relationship used for Internal resistance. Convert units first and explain what the calculated result means.
Brighter light lowers the upper LDR resistance. The fixed lower resistor then forms a larger fraction of total resistance, so the output across it increases.
Watch for: Do not substitute numbers before stating the relationship used for Potential dividers. Convert units first and explain what the calculated result means.
In a transverse wave, oscillations are perpendicular to the direction of energy transfer. In a longitudinal wave, oscillations are parallel and form compressions and rarefactions.
Watch for: Do not substitute numbers before stating the relationship used for Wave motion. Convert units first and explain what the calculated result means.
Electromagnetic-wave speed changes at the boundary. Frequency is set by the source and remains constant, so wavelength changes; an oblique wavefront therefore changes direction.
Watch for: Do not substitute numbers before stating the relationship used for Electromagnetic waves. Convert units first and explain what the calculated result means.
Superposition states that resultant displacement is the algebraic sum of individual displacements. Measuring individual and combined signals as path difference changes tests constructive and destructive addition.
Watch for: Do not substitute numbers before stating the relationship used for Superposition. Convert units first and explain what the calculated result means.
Both involve oscillations, wavelength and frequency. Opposite energy flows cancel in an ideal stationary wave, whereas a progressive wave carries energy in its propagation direction.
Watch for: Do not substitute numbers before stating the relationship used for Stationary waves. Convert units first and explain what the calculated result means.
The photon model assigns each photon a discrete energy E = hf. Energy exchange occurs in whole photons rather than arbitrary fractions of one photon.
Watch for: Do not substitute numbers before stating the relationship used for Photons. Convert units first and explain what the calculated result means.
Ultraviolet photons can transfer enough energy to surface electrons for emission, so negative charge leaves and the leaf collapses. The threshold behaviour supports photons.
Watch for: Do not substitute numbers before stating the relationship used for The photoelectric effect. Convert units first and explain what the calculated result means.
A beam of electrons produces an interference/diffraction pattern, which is a wave phenomenon. Detection remains localised, so the result supports wave–particle duality.
Watch for: Do not substitute numbers before stating the relationship used for Wave-particle duality. Convert units first and explain what the calculated result means.
A material thermometer relies on a property such as volume or resistance. Thermodynamic temperature is defined independently of any particular working substance and has an absolute zero.
Watch for: Do not substitute numbers before stating the relationship used for Temperature. Convert units first and explain what the calculated result means.
At the melting point, supplied energy changes the particles' potential energy and arrangement rather than raising temperature. The temperature remains constant until the change of state is complete.
Watch for: Do not substitute numbers before stating the relationship used for Solid, liquid and gas. Convert units first and explain what the calculated result means.
Close contact improves transfer from heater to block and helps the thermometer represent the block temperature. Insulation is still needed because losses cannot be eliminated completely.
Watch for: Do not substitute numbers before stating the relationship used for Thermal properties of materials. Convert units first and explain what the calculated result means.
The model assumes point-like particles, random motion, negligible intermolecular forces except during collisions, and perfectly elastic collisions. A distribution of speeds is expected.
Watch for: Do not substitute numbers before stating the relationship used for Ideal gases. Convert units first and explain what the calculated result means.
Angular velocity is angular displacement per unit time: ω = 18/3.0 = 6.0 rad s⁻¹.
Watch for: Do not substitute numbers before stating the relationship used for Kinematics of circular motion. Convert units first and explain what the calculated result means.
Velocity is a vector, so changing direction means acceleration even at constant speed. A centripetal resultant force acts toward the centre while instantaneous velocity is tangential.
Watch for: Do not substitute numbers before stating the relationship used for Centripetal force. Convert units first and explain what the calculated result means.
In ideal SHM, angular frequency is set by system parameters such as k/m or g/L in the small-angle model, not by amplitude. The oscillator is isochronous.
Watch for: Do not substitute numbers before stating the relationship used for Simple harmonic oscillations. Convert units first and explain what the calculated result means.
At equilibrium speed is maximum and spring extension from equilibrium is zero. At x = ±A speed is zero and elastic potential energy is maximum.
Watch for: Do not substitute numbers before stating the relationship used for Energy of a simple harmonic oscillator. Convert units first and explain what the calculated result means.
A free system oscillates after an initial disturbance at or near its natural frequency. A system receiving continuing periodic energy from an external driver undergoes forced oscillation.
Watch for: Do not substitute numbers before stating the relationship used for Damping. Convert units first and explain what the calculated result means.
Gravitational field strength is force per unit mass and electric field strength is force per unit positive charge. Both are vector fields, although electric forces may attract or repel.
Watch for: Do not substitute numbers before stating the relationship used for Point and spherical masses. Convert units first and explain what the calculated result means.
Across a few metres, the fractional change in distance from Earth's centre is extremely small, so both magnitude and direction of g are effectively constant.
Watch for: Do not substitute numbers before stating the relationship used for Newton's law of gravitation. Convert units first and explain what the calculated result means.
Matching Earth's angular velocity above the equator in the same direction keeps the satellite above one longitude. This supports fixed satellite dishes and continuous regional communication.
Watch for: Do not substitute numbers before stating the relationship used for Planetary motion. Convert units first and explain what the calculated result means.
Gravity attracts. A mass at finite distance is bound and has less potential energy than at infinity, so its potential relative to zero at infinity is negative.
Watch for: Do not substitute numbers before stating the relationship used for Gravitational potential and energy. Convert units first and explain what the calculated result means.
Gravity contracts gas and dust, converting potential energy to thermal energy. At sufficiently high core temperature, hydrogen fusion supplies energy; hydrostatic equilibrium then balances inward gravity and outward pressure.
Watch for: Do not substitute numbers before stating the relationship used for Stars. Convert units first and explain what the calculated result means.
Atomic electrons occupy discrete energy levels. A transition to a lower level emits one photon whose energy equals the difference between the two levels, producing a characteristic frequency.
Watch for: Do not substitute numbers before stating the relationship used for Electromagnetic radiation from stars. Convert units first and explain what the calculated result means.
Observations indicated that the universe's expansion is accelerating rather than slowing under gravity alone. Dark energy is the name given to the proposed cause, although its nature remains uncertain.
Watch for: Do not substitute numbers before stating the relationship used for Cosmology. Convert units first and explain what the calculated result means.
The charging model predicts V against t. A high-resistance sensor minimises loading; regular time-stamped readings allow the exponential approach to the supply to be tested safely.
Watch for: Do not substitute numbers before stating the relationship used for Capacitors. Convert units first and explain what the calculated result means.
A capacitor stores electrical energy in its field. A charging circuit supplies this over time; a low-resistance discharge path can then deliver the energy in a short intense pulse.
Watch for: Do not substitute numbers before stating the relationship used for Energy. Convert units first and explain what the calculated result means.
During discharge Q and V = Q/C decrease exponentially. With fixed R, I = V/R therefore also decreases exponentially.
Watch for: Do not substitute numbers before stating the relationship used for Charging and discharging capacitors. Convert units first and explain what the calculated result means.
Electric-field direction is the direction of force on a positive test charge. Around a positive isolated sphere, field lines point radially outward and become more widely spaced with distance.
Watch for: Do not substitute numbers before stating the relationship used for Point and spherical charges. Convert units first and explain what the calculated result means.
Their mathematical forms are analogous: g is proportional to M/r² and E to Q/r². Mass is effectively one sign, so gravity attracts; electric charge has two signs.
Watch for: Do not substitute numbers before stating the relationship used for Coulomb's law. Convert units first and explain what the calculated result means.
F = qE. For an electron q = −e, so acceleration is downward and constant while horizontal velocity remains constant, giving projectile-like parabolic motion.
Watch for: Do not substitute numbers before stating the relationship used for Uniform electric field. Convert units first and explain what the calculated result means.
Potential is potential energy per unit positive charge relative to zero at infinity, equivalently the external work per coulomb in quasistatic transfer from infinity.
Watch for: Do not substitute numbers before stating the relationship used for Electric potential and energy. Convert units first and explain what the calculated result means.
Reversing either the current or the magnetic field reverses the forces on the coil sides, so the turning direction reverses. Reversing both would leave the rotation direction unchanged.
Watch for: Do not substitute numbers before stating the relationship used for Magnetic fields. Convert units first and explain what the calculated result means.
BQv = mv²/r acts toward the circle centre. Because force is perpendicular to displacement, magnetic work is zero and kinetic energy and speed remain constant.
Watch for: Do not substitute numbers before stating the relationship used for Motion of charged particles. Convert units first and explain what the calculated result means.
An alternating primary current produces changing flux in the iron core. This changing flux links the secondary coil and induces an alternating potential difference.
Watch for: Do not substitute numbers before stating the relationship used for Electromagnetism. Convert units first and explain what the calculated result means.
Most alpha particles passed through, but rare large deflections required a tiny dense positive nucleus. Subsequent evidence established protons, neutrons and electron energy levels.
Watch for: Do not substitute numbers before stating the relationship used for The nuclear atom. Convert units first and explain what the calculated result means.
Leptons are fundamental in this model and participate in the weak interaction. Charged leptons also experience electromagnetic interaction, but not the strong force.
Watch for: Do not substitute numbers before stating the relationship used for Fundamental particles. Convert units first and explain what the calculated result means.
Irradiation is exposure to radiation from an external source and stops when the source is removed. Contamination means radioactive atoms are present on or inside the object and continue emitting until removed or decayed.
Watch for: Do not substitute numbers before stating the relationship used for Radioactivity. Convert units first and explain what the calculated result means.
Positive nuclei repel. Extremely high temperature supplies kinetic energy for close approach, while adequate density and confinement are needed long enough for useful fusion without losing more energy than is produced.
Watch for: Do not substitute numbers before stating the relationship used for Nuclear fission and fusion. Convert units first and explain what the calculated result means.
Tomographic reconstruction avoids superposition that obscures a projection image and can improve localisation and contrast. The benefit must be weighed against generally greater radiation exposure and cost.
Watch for: Do not substitute numbers before stating the relationship used for Using X-rays. Convert units first and explain what the calculated result means.
The tracer's biochemical uptake relates activity to function. After positron annihilation, nearly opposite gamma photons detected in coincidence define a line of response; many events reconstruct the distribution.
Watch for: Do not substitute numbers before stating the relationship used for Diagnostic methods in medicine. Convert units first and explain what the calculated result means.
Echo time gives depth and amplitude indicates reflection strength. A single line produces an A-scan; scanning many directions and encoding amplitude as brightness produces a B-scan.
Watch for: Do not substitute numbers before stating the relationship used for Using ultrasound. Convert units first and explain what the calculated result means.
No matching topics. Try another search.
OCR · Physics A · A Level · Physics · H556
Version 3.0, March 2026; current checked 28 August 2026
Source checked: 2026-08-28. The current official specification controls assessment requirements and option choices.
Yes. This page offers three original questions from three different skills on this exact course. Each answer has an explanation, followed by a sample heatmap showing what was correct and what to revisit. No account is needed, and taster answers are not saved.
It shows the outcome of these three answers and gives a specific skill to discuss or practise next. It is not a full assessment, a mastery score or a grade prediction. Broader practice over time is needed to understand progress.
LearningP currently maps 74 assessed areas for specification H556. The visible topic map below is derived from the verified route; the current official specification remains controlling.
The verified source bank contains 843 original LearningP question records for this route. Every mapped area meets the current publication minimum and passed the latest blocker and review audit.
No. LearningP uses official specifications and assessment materials to map content and demand, while its practice questions and explanations are independently authored.
No. LearningP reports practice evidence, coverage, strengths and gaps. It does not guarantee or automatically predict examination outcomes.
Use the official OCR · Physics A specification and assessment-resource pages linked on this page, together with information supplied by the learner’s school.