고등학생 물리학을 간단하게 – 파동과 빛 1/2부

This session will take seven (7) classes to complete. It will deal with the following:-

1.	Class 1 – What are waves and how are they produced
2.	Class 2 & 3 – Wave Characteristics
3.	Class 4 & 5 – Sound as Wave Motion
4.	Class 6 & 7 – Electromagnetic Waves.


1.	What are waves and how are they produced

a.	recall the nature of a vibration or an oscillation
b.	understand how a pulse is produced by an oscillating object
c.	appreciate that a wave is a set of continuous pulses
d.	describe the production of waves using springs and ripple tanks
e.	distinguish between the two basic types of wave – transverse and longitudinal
f.	recall the reason why some transverse waves and some longitudinal waves are described as progressive waves or travelling waves
g.	recall that all waves transmit energy originating at their source
h.	recall that some waves (called matter waves) need a medium (matter) for propagation, while others (electromagnetic waves) do not and can travel in a vacuum
i.	recall that all longitudinal waves need a medium for propagation
j.	draw diagrams to represent transverse waves
k.	draw diagrams to represent longitudinal waves
l.	represent transverse waves and longitudinal waves on displacement–position graphs
m.	represent transverse waves and longitudinal waves on displacement–time graphs
n.	use straight lines to represent the direction of energy flow (rays)


2.	Wave Characteristics

a.	define and use the following terms: frequency, period, wavelength, displacement, amplitude, phase, phase difference, path difference, wavefront, wave speed
b.	explain the meanings of and use the expressions ‘in phase’ and ‘out of phase’
c.	recall the relationship between the amplitude and the energy of a wave
d.	recall and use the relationship v = f λ, where v is the wave speed, f is the frequency, and λ is the wavelength


3.	Sound as Wave Motion

a.	recall that sound is a longitudinal vibration and therefore requires a medium for propagation
b.	recall that sound may be produced by vibrating systems
c.	explain why a medium transmitting sound waves must be elastic
d.	describe how sound is propagated in a medium
e.	recall that sound waves show the effects of reflection, refraction, diffraction and interference
f.	cite evidence that sound waves undergo reflection and refraction and show diffraction and interference effects
g.	describe an experiment to show that sound is not transmitted through a vacuum
h.	describe a simple experiment to estimate the speed of sound in air
i.	recall the order of size of the speed of sound in air and apply this knowledge to practical situations
j.	recall that the speed of sound in a given medium depends on physical properties of the medium such as stiffness and density
k.	use the terms ‘pitch’ and ‘loudness’ and relate them to wave parameters
l.	recall the range of frequencies normally detectable by the human ear
m.	recall that ultrasound has a higher range of frequencies than ordinary sound, but is inaudible to the human ear
n.	recall the uses of ultrasound


4.	Electromagnetic Waves

a.	describe the circumstances in which electromagnetic waves are produced
b.	describe the nature of electromagnetic waves
c.	recall that all electromagnetic waves travel at the same speed in a vacuum
d.	recall that the speed of electromagnetic waves in a medium varies with the nature of the medium
e.	recall that the temperature of the Sun is several thousands of degrees Celsius
f.	recall that the electromagnetic waves emitted by the Sun have a very wide continuous range of frequencies and therefore a continuous range of wavelengths
g.	recall that this continuous range of frequencies (called the continuous electromagnetic spectrum) can be subdivided into smaller continuous spectra, each with a characteristic range of frequencies and wavelengths
h.	remember that these different types of spectra do not have sharp boundaries but overlap with their neighbours
i.	recall that the waves of each of these smaller spectra, if they do interact with matter, show particular physical effects when they do
j.	recall that the radiation in each of these smaller spectra is produced in a particular way
k.	understand that because of these effects the different types of electromagnetic radiation have particular uses