Tips On Problem Solving In Examinations

Learning objectives

• Use SI quantities, units, prefixes and dimensional analysis.
• Estimate physical quantities and check the reasonableness of results.
• Assess random, systematic and propagated uncertainties.
• Resolve, add and subtract coplanar vectors.
• Explain inertia and momentum, then apply Newton's laws using free-body diagrams.
• Describe normal, frictional, buoyant and viscous forces qualitatively.
• Apply Hooke's law within the limit of proportionality.
• Apply moments, couples and force-and-torque equilibrium using free-body diagrams and vector triangles.
• show an understanding that the weight of a body may be taken as acting at a single point known as its centre of gravity
• apply the principle of moments to new situations or to solve related problems
• Interpret position, displacement, velocity and acceleration using equations and graphs.
• Derive the uniformly accelerated motion equations from the definitions of velocity and acceleration.
• Derive and apply uniformly accelerated motion equations with a stated sign convention.
• Track energy stores and transfers, then apply conservation of energy.
• Define work and derive and apply the kinetic-energy relationship.
• Derive Eₖ = ½mv² from the definition of work done by a force and the uniformly accelerated motion equations.
• Represent fields and relate work done by a field to potential-energy change.
• Draw field-line representations of uniform and radial gravitational and electric fields.
• Use force–extension graphs to determine elastic potential energy.
• Apply power, mechanical power and efficiency relationships.
• Relate weight and gravitational potential energy changes in a uniform gravitational field.
• Analyse projectile motion by separating perpendicular components.
• Explain falling motion with air resistance using forces, energy and terminal velocity.
• Use impulse and momentum conservation in one-dimensional elastic and inelastic collisions.
• Express angular displacement in radians and use s = rθ.
• Relate angular velocity, period, frequency and tangential speed using v = rω.
• Explain and apply centripetal acceleration and resultant-force relationships.
• Apply Newton's law of gravitation to point and spherical masses.
• Derive and apply gravitational field strength, including the near-surface model.
• Derive the gravitational field strength due to a point mass from Newton's law of gravitation and the definition of field strength.
• Relate gravitational potential, potential energy and field gradient.
• Analyse escape speed using conservation of energy.
• Analyse circular gravitational orbits and geostationary satellite conditions.
• Use oscillation quantities and describe free oscillations and their investigation.
• Relate displacement, velocity, acceleration and phase in simple harmonic motion.
• Identify and analyse simple harmonic motion using its defining equation and sinusoidal solutions.
• Describe kinetic–potential energy interchange in ideal simple harmonic motion.
• Compare light, critical and heavy damping and explain critical-damping applications.
• Distinguish free and forced oscillations, natural frequency and driving frequency.
• Interpret resonance response curves, damping effects and practical applications.
• Describe wave models, use wave quantities and interpret wave graphs in space and time.
• Relate phase difference to separations in time and position.
• Use wave intensity, amplitude and inverse-square relationships with their assumptions.
• Explain polarisation and apply Malus’ law to amplitude and intensity.
• Apply the principle of superposition to resultant displacement.
• Explain standing-wave formation, nodes, antinodes and energy transfer.
• Apply boundary conditions to standing waves on stretched strings.
• Analyse displacement and pressure patterns in resonant air columns and determine sound wavelength.
• Explain single-aperture diffraction and apply first-minimum and Rayleigh criteria.
• Explain coherent two-source interference using phase and path difference.
• Analyse Young double-slit interference and its small-angle assumptions.
• Use diffraction gratings to analyse principal maxima and determine wavelength.
• Use thermodynamic temperature and convert between Celsius and kelvin.
• Use ideal-gas equations with particles, moles and SI units.
• Apply the kinetic model to gas pressure and mean translational kinetic energy.
• Derive pV = ⅓Nm⟨c²⟩ from the definition of pressure and a one-dimensional model of molecular collisions extended to three dimensions.
• Relate microscopic energy, internal energy and thermal equilibrium.
• Apply work conventions and the zeroth and first laws of thermodynamics.
• Define and use heat capacity and specific heat capacity in energy balances.
• Define and use specific latent heat in phase-change energy balances.
• Apply Coulomb's law to the force between point charges.
• Define electric field strength and calculate resultant fields due to point charges.
• Define electric potential and calculate potential due to point charges.
• Relate electric potential, potential energy and work for systems of point charges.
• Use the negative potential gradient and relate equipotentials to field lines.
• Calculate field strength and force in uniform electric fields.
• Analyse charged-particle motion in uniform electric fields.
• Apply capacitance and capacitor-energy relationships.
• Relate current to charge flow, number density and drift velocity.
• Apply potential difference, e.m.f. and electrical power relationships.
• Represent sinusoidal a.c. and use peak and r.m.s. values.
• Analyse mean power in resistive a.c. loads and half-wave rectification.
• Recall circuit symbols and draw or interpret circuit diagrams.
• Draw circuit diagrams containing sources, switches, resistors, meters, lamps, thermistors, light-dependent resistors and diodes.
• Apply resistance and resistivity, interpret I–V characteristics and explain temperature effects.
• Analyse e.m.f., terminal potential difference and internal resistance in real sources.
• Analyse series, parallel and potential-divider resistor networks.
• Combine capacitors in series and parallel.
• Analyse charging and discharging in RC circuits using the time constant.
• Calculate and represent magnetic fields produced by currents.
• Sketch magnetic field lines due to currents in a long straight wire, a flat circular coil and a long solenoid.
• Analyse forces on current-carrying conductors, current balances and interactions between parallel currents.
• Analyse forces and paths of moving charges in uniform fields.
• Apply crossed electric and magnetic fields to velocity selection.
• Use magnetic flux and flux-linkage relationships.
• Apply Faraday's and Lenz's laws to induced e.m.f. and direction.
• Explain simple applications of electromagnetic induction, including motional e.m.f. and eddy currents.
• Explain simple iron-core transformer operation and apply ideal transformer ratios.
• Use photon energy and momentum and analyse the photoelectric effect.
• Apply de Broglie wavelength and wave-particle evidence.
• Interpret wavefunctions, probability density and superposition.
• Apply uncertainty and infinite-square-well energy quantisation.
• Analyse atomic energy levels and emission or absorption spectra.
• Interpret nuclear structure, isotopes and Rutherford scattering.
• Analyse random radioactive decay, activity, decay constant and half-life.
• Relate binding energy per nucleon to fission, fusion, applications and hazards.
• Apply conservation laws to nuclear equations and beta decay, including antineutrino evidence.
• Use mass-energy equivalence, mass defect and binding energy.
• Use techniques and apparatus safely and effectively, and make and record precise observations and measurements
• Analyse practical data, graphs, gradients and intercepts
• Evaluate practical limitations and propose specific improvements
• Plan a practical investigation with controlled variables and a workable method