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Unit 2: Check List Waves – Nature of Waves:

Explain what is a wave

Understand what is a progressive wave

Define the terms:

amplitude

displacement

wavelength

time period

frequency

phase difference

wavefront and rays

path difference

Learn and derive the wave equation linking wave speed, frequency and wavelength

Understand what are transverse waves and longitudinal waves

Understand the different types of wave propagation: circular, plane continuous, trains and pulse waves

Waves – Wave Behaviour:

Understand and define the following wave properties:

reflection

refraction

define refractive index

understand what is the normal

clearly understand the calculations involving refraction of light

understand the difference between absolute refractive index and relative refractive index

define total internal reflection

learn the conditions for total internal reflection

explain how optical fibres work

diffraction

learn when diffraction is maximum

understand when diffraction is required

describe the diffraction of light through a narrow slit

define fringe and fringe width

describe diffraction with electrons

polarisation (applicable only for transverse waves)

understand that only transverse waves can be polarised

understand that when light is reflected off from a surface it is partially polarised

experiment to detect polarisation angle (how materials rotate the plane of polarisation)

understand the application of polarisation e.g., for stress analysis, radio and TV signals, etc

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Unit 2: Check List Waves – Wave Behaviour (concluded):

interference

define superposition

understand and explain the principle of superposition of waves

link interference with superposition

understand that interference could be constructive or destructive

define and explain phase difference and path difference

understand that constructive or destructive interference depends on the path difference

learn the equations for path difference for constructive or destructive interference

define coherence

understand that the condition for interference is coherence of two or more sources of waves

understand what is a diffraction grating

understand interference of light waves through diffraction grating

understand the effect of more slits on interference patterns

understand the effect of monochromatic light on a diffraction grating

learn the equation for interference and draw conclusions from and

understand the effect of shining white light through a diffraction grating

define a stationary wave

understand the condition for a stationary wave

state the difference between stationary waves and progressive waves

define and understand the terms nodes and antinodes

learn the experiment demonstrating standing waves with microwaves and sound waves

explain the terms harmonic and overtones in musical instruments such as guitars and air columns

remember where nodes and antinodes form in guitar strings and air columns

Waves – Wave Applications:

Understand ultrasound imaging

Understand how ultrasound waves are reflected and transmitted at interfaces

Understand how reflection of ultrasound is used in ultrasound scans

Understand the term resolution

Understand how shorter wavelengths and shorter pulses produce clearer images

Understand why ultrasound is transmitted in pulses

Understand what is the Doppler effect

Explain how the speed of moving objects can be measured using the Doppler effect

Learn the properties of the electromagnetic spectrum

Learn the variation in properties of the components in the EM Spectrum

Learn the effects of different radiations on the body

3

Unit 2: Check List DC Electricity – Charge and Current:

Define charge

Understand the types of charge that exists

Describe the nature of charged objects

Learn the unit for charge

Define an electric current

Learn the equation of an electric current

Learn the unit for electric current

Explain the direction of conventional current flow and direction of electron flow

Explain what are charge carriers conducting an electric current [ definition of charge carrier and relevant examples]

Define drift velocity of charge carriers [ explanation of what causes the charge carriers to drift]

Explain why drift velocity is an average velocity and stays the same in a conductor

Explain how the current depends on the drift velocity using the transport equation

Explain how a light bulb comes on instantly when the switch is turned even when the drift velocity of electrons is only a

fraction of a millimetre per second

Understand that different materials have different numbers of charge carriers and explain how they conduct using the

transport equation

DC Electricity – Potential difference, electromotive force and power:

Define potential difference with formula and units

Define electromotive force with formula and units

Define voltage

Define electrical energy and power in terms of current and voltage with formula and units

DC Electricity – Current-potential difference relationships [I/V Characteristics]:

Explain how rheostat and potentiometer works

Explain how current and voltage can be regulated using a rheostat or potentiometer

Remember the circuit diagrams on making a rheostat or a potentiometer using a variable resistor and how they can be

used to investigate I-V characteristics of conductors

Show the I-V characteristics for :

metallic conductor

tungsten filament

semiconductor diode

4

Unit 2: Check List DC Electricity – Resistance and resistivity:

Define resistance

Define Ohm’s law

Understand that for an Ohmic conductor the resistor is constant

Define resistivity

Explain how resistivity and resistance are connected by the equation

Show the R-V characteristics for :

metallic conductor

tungsten filament

semiconductor diode

Explain the effect of temperature on the resistivity of a metal using the transport equation

Explain the effect of temperature on the resistivity of a tungsten filament using the transport equation

Explain the effect of temperature on the resistivity of a semiconductor using the transport equation

DC Electricity – Electric Circuits:

Explain Kirchhoff’s First law and how it relates to the law of conservation of charge

Explain Kirchhoff’s Second law and how it relates to the law of conservation of energy

Explain internal resistance

Derive the equation connecting emf., terminal p.d., resistance, internal resistance and current using the law of

conservation of energy in a circuit

Draw the graph of terminal voltage against current

Explain why a battery runs out of charge

Explain why a voltmeter is placed parallel in a circuit

Explain why an ammeter is placed in series in a circuit

Derive the equation of total resistance in a series circuit

Derive the equation of total resistance in a parallel circuit

Explain how a potential divider works

Derive the equation for getting Vout from a potential divider circuit

Explain what is a NTC thermistors and an LDR (light dependant resistor)

Explain the applications of potential divider using thermistors and LDRs.

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Unit 2: Check List Nature of Light – Nature of Light:

Understand that radiation flux is the intensity of light [amount of energy landing on a unit area in a unit time]

Learn the formula for radiation flux and its unit

Understand that light behaves like a wave as well as a particle

Understand what is a quantisation of light

Understand that photon is a quantum of light

Understand what is the electron-volt

Understand that photon energies are usually given in electron volts

Understand that photons are released from electrons in atoms when they are excited

Explain what is line spectrum, emission spectrum, continuous spectra and absorption spectra

Understand that the different spectra indicate the energy levels of an atom

Understand the photoelectric effect

Learn why the wave theory of light cannot explain the photoelectric effect

Explain how the photon model of light can explain the photoelectric effect

Learn and explain the photoelectric equation

Understand that the photoelectric equation is a result of the law of conservation of energy

Explain and define each term of the photoelectric equation

Understand how the phototube can be used to find the sopping potential

Understand the wave-particle duality