6PH02 Physics at Work

Revision videos


28 understand and use the terms amplitude, frequency, period, speed and wavelength
29 identify the different regions of the electromagnetic spectrum and describe some of their applications
30 use the wave equation v = f \lambda
31 recall that a sound wave is a longitudinal wave which can be described in terms of the displacement of molecules
32 use graphs to represent transverse and longitudinal waves, including standing waves
33 explain and use the concepts of wavefront, coherence, path difference, superposition and phase
34 recognise and use the relationship between phase difference and path difference
35 explain what is meant by a standing (stationary) wave, investigate how such a wave is formed, and identify nodes and antinodes
36 recognise and use the expression for refractive index _1mu_2 = \frac{\sin i}{\sin r} = v_1/v_2, determine refractive index for a material in the laboratory, and predict whether total internal reflection will occur at an interface using critical angle
37 investigate and explain how to measure refractive index
38 discuss situations that require the accurate determination of refractive index
39 investigate and explain what is meant by plane polarised light
40 investigate and explain how to measure the rotation of the plane of polarisation
41 investigate and recall that waves can be diffracted and that substantial diffraction occurs when the size of the gap or obstacle is similar to the wavelength of the wave
42 explain how diffraction experiments provide evidence for the wave nature of electrons
43 discuss how scientific ideas may change over time, for example, our ideas on the particle/wave nature of electrons
44 recall that, in general, waves are transmitted and reflected at an interface between media
45 explain how different media affect the transmission/reflection of waves travelling from one medium to another
46 explore and explain how a pulse-echo technique can provide details of the position and/or speed of an object and describe applications that use this technique
47 explain qualitatively how the movement of a source of sound or light relative to an observer/detector gives rise to a shift in frequency (Doppler effect) and explore applications that use this effect
48 explain how the amount of detail in a scan may be limited by the wavelength of the radiation or by the duration of pulses
49 discuss the social and ethical issues that need to be considered, eg, when developing and trialling new medical techniques on patients or when funding a space mission


DC Electricity

50 describe electric current as the rate of flow of charged particles and use the expression I = \frac{\Delta Q}{\Delta t}
51 use the expression V = \frac{W}{Q}
52 recognise, investigate and use the relationships between current, voltage and resistance, for series and parallel circuits, and know that these relationships are a consequence of the conservation of charge and energy
53 investigate and use the expressions P = VI, W = VIt. Recognise and use related expressions eg P = I^2R and P = \frac{V^2}{R}
54 use the fact that resistance is defined by R = \frac{V}{I} and that Ohm’s law is a special case when I \propto V
55 demonstrate an understanding of how ICT may be used to obtain current-potential difference graphs, including non-ohmic materials and compare this with traditional techniques in terms of reliability and validity of data
56 interpret current-potential difference graphs, including non-ohmic materials
57 investigate and use the relationship R = \frac{\rho l}{A}
58 investigate and explain how the potential along a uniform current-carrying wire varies with the distance along it and how this variation can be made use of in a potential divider
59 define and use the concepts of emf and internal resistance and distinguish between emf and terminal potential difference
60 investigate and recall that the resistance of metallic conductors increases with increasing temperature and that the resistance of negative temperature coefficient thermistors decreases with increasing temperature
61 use I = nqvA to explain the large range of resistivities of different materials
62 explain, qualitatively, how changes of resistance with temperature may be modelled in terms of lattice vibrations and number of conduction electrons


Nature of light

63 explain how the behaviour of light can be described in terms of waves and photons
64 recall that the absorption of a photon can result in the emission of a photoelectron
65 understand and use the terms threshold frequency and work function and recognise and use the expression hf = fi + \frac{1}{2} mv^2_{max}
66 use the non-SI unit, the electronvolt (eV) to express small energies
67 recognise and use the expression E = hf to calculate the highest frequency of radiation that could be emitted in a transition across a known energy band gap or between known energy levels
68 explain atomic line spectra in terms of transitions between discrete energy levels
69 define and use radiation flux as power per unit area
70 recognise and use the expression \mbox{efficiency} = \frac{\mbox{useful energy (or power) output}}{\mbox{total energy (or power) input}}
71 explain how wave and photon models have contributed to the understanding of the nature of light
72 explore how science is used by society to make decisions, for example, the viability of solar cells as a replacement for other energy sources, the uses of remote sensing