Unit 4: Further Mechanics, Fields and Particles
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4.3 - Further Mechanics
4.3.81Impulse and change of momentum
Understand how to use the equation impulse = F∆t =∆p (Newton’s second law of motion)
4.3.82Core Practical 9 - force and momentum change
CORE PRACTICAL 9: Investigate the relationship between the force exerted on an object and its change of momentum
4.3.83Momentum conservation in two dimensions
Understand how to apply conservation of linear momentum to problems in two dimensions
4.3.84Core Practical 10 - ICT collision analysis
CORE PRACTICAL 10: Use ICT to analyse collisions between small spheres, e.g. ball bearings on a table top
4.3.85Elastic and inelastic collisions
Determine whether a collision is elastic or inelastic.
4.3.86Kinetic energy from momentum
Derive and use Ek = p²/(2m) for the kinetic energy of a non-relativistic particle.
4.3.87Angular displacement
Be able to express angular displacement in radians and in degrees, and convert between these units
4.3.88Angular velocity
Understand angular velocity and use v = ωr and T = 2π/ω.
4.3.89Centripetal acceleration derivation
Use vector diagrams to derive centripetal acceleration a = v²/r = rω² and apply these equations.
4.3.90Centripetal force requirement
Understand that a resultant centripetal force is required to produce and maintain circular motion.
4.3.91Centripetal force equations
Use centripetal force F = ma = mv²/r = mrω².
4.4 - Electric and Magnetic Fields
4.4.92Electric fields
Understand that an electric field is a region where a charged particle experiences a force.
4.4.93Electric field strength
Understand electric field strength E = F/Q and use this relationship.
4.4.94Coulomb’s law
Use Coulomb's law F = Q1Q2/(4πε0r²) for the force between two point charges.
4.4.95Electric field due to a point charge
Use E = Q/(4πε0r²) for the electric field due to a point charge.
4.4.96Electric field and electric potential
Know and understand the relationship between electric field and electric potential.
4.4.97Uniform electric field between plates
Use E = V/d for a uniform electric field between parallel plates.
4.4.98Electric potential in a radial field
Use V = Q/(4πε0r) for electric potential in a radial field.
4.4.99Field lines and equipotentials
Draw and interpret field-line and equipotential diagrams for radial and uniform electric fields.
4.4.100Capacitance
Understand capacitance C = Q/V and use this relationship.
4.4.101Energy stored by a capacitor
Use W = ½QV for capacitor energy, derive it from the area under a potential-difference–charge graph, and derive and use W = ½CV² and W = Q²/(2C).
4.4.102Capacitor charge and discharge curves
Be able to draw and interpret charge and discharge curves for resistor capacitor circuits and understand the significance of the time constant RC
4.4.103Core Practical 11 - capacitor charging and discharging
CORE PRACTICAL 11: Use an oscilloscope or data logger to display and analyse the potential difference (p.d.) across a capacitor as it charges and discharges through a resistor
4.4.104Capacitor discharge equations
Use Q = Q0e^(−t/RC), I = I0e^(−t/RC), and V = V0e^(−t/RC) for capacitor discharge, and derive and use ln Q = ln Q0 − t/RC, ln I = ln I0 − t/RC, and ln V = ln V0 − t/RC.
4.4.105Magnetic flux density, flux and flux linkage
Understand and use the terms magnetic flux density B, flux φ and flux linkage Nφ
4.4.106Force on a moving charge in a magnetic field
Be able to use the equation F = Bqv sinθ and apply Fleming’s left-hand rule to charged particles moving in a magnetic field
4.4.107Force on a current-carrying conductor
Be able to use the equation F = BIl sinθ and apply Fleming’s left-hand rule to current carrying conductors in a magnetic field
4.4.108Induced e.m.f. from magnet-coil motion
Understand the factors affecting the e.m.f. induced in a coil when there is relative motion between the coil and a permanent magnet
4.4.109Induced e.m.f. from linked coils
Understand the factors affecting the e.m.f. induced in a coil when there is a change of current in another coil linked with this coil
4.4.110Faraday’s and Lenz’s laws
Use Faraday's law to determine induced e.m.f. and use the combined Faraday–Lenz equation ε = −d(NΦ)/dt.
4.5 - Nuclear and Particle Physics
4.5.111Nucleon number and proton number
Understand what is meant by nucleon number (mass number) and proton number (atomic number)
4.5.112Alpha scattering and the nuclear atom
Understand how large-angle alpha particle scattering gives evidence for a nuclear model of the atom and how our understanding of atomic structure has changed over time
4.5.113Thermionic emission and acceleration
Understand that electrons are released in the process of thermionic emission and how they can be accelerated by electric and magnetic fields
4.5.114Fields in particle accelerators and detectors
Understand the role of electric and magnetic fields in particle accelerators, including linacs and cyclotrons, and in detectors through ionisation and deflection.
4.5.115Charged-particle radius in a magnetic field
Derive and use r = mv/(BQ) for the radius of a charged particle moving perpendicular to a magnetic field.
4.5.116Particle interaction conservation laws
Be able to apply conservation of charge, energy and momentum to interactions between particles and interpret particle tracks
4.5.117High energies and nucleon structure
Understand why high energies are required to investigate the structure of nucleons
4.5.118Mass-energy equivalence
Be able to use the equation ∆E = c2∆m in situations involving the creation and annihilation of matter and antimatter particles
4.5.119Particle energy and mass units
Be able to use MeV and GeV (energy) and MeV/c2, GeV/c2 (mass) and convert between these and SI units
4.5.120Relativistic lifetime increase
Understand situations in which the relativistic increase in particle lifetime is significant (use of relativistic equations not required)
4.5.121Standard quark-lepton model
Know that in the standard quark-lepton model particles can be classified as: • baryons (e.g. neutrons and protons), which are made from three quarks • mesons (e.g. pions), which are made from a quark and an antiquark • leptons (e.g. electrons and neutrinos), which are fundamental particles • photons and that the symmetry of the model predicted the top quark
4.5.122Particles and antiparticles
Know that every particle has a corresponding antiparticle and be able to use the properties of a particle to deduce the properties of its antiparticle and vice versa
4.5.123Charge, baryon and lepton number conservation
Understand how to use laws of conservation of charge, baryon number and lepton number to determine whether a particle interaction is possible
4.5.124Particle equations
Be able to write and interpret particle equations given the relevant particle symbols.