Physics Topic: Quantum Mechanics
-
Show an appreciation of the particulate nature of electromagnetic radiation.
-
Recall and use E = hf.
-
Show an understanding that the photoelectric effect provides evidence for a particulate nature of electromagnetic radiation while phenomena such as interference and diffraction provide evidence for a wave nature.
-
Recall the significance of the threshold frequency.
-
Recall and use the equation 1/2m(vmax)2 = eVs, where Vs is the stopping potential.
-
Explain photoelectric phenomena in terms of photon energy and work function energy.
-
Explain why the maximum photoelectric energy is independent of intensity whereas the photoelectric current is proportional to intensity.
-
Recall, use and explain the significance of hf = f + 1/2m(vmax)2.
-
Describe and interpret qualitatively the evidence provided by electron diffraction for the wave nature of particles.
-
Recall and use the relation for the de Broglie wavelength = h/p.
-
Show an understand of the existence of discrete electron energy levels in isolated atoms (e.g. atomic hydrogen) and deduce how this leads to spectral lines.
-
Distinguish between emission and absorption line spectra.
-
Recall and use the relation hf = E1 – E2.
For H2 syllabus only:
-
Explain the origins of the features of a typical X-ray spectrum using quantum theory.
-
Show an understanding of and apply the Heisenberg position-momentum and time-energy uncertainty principles in new situations or to solve related problems.
-
Show an understanding that an electron can be described by a wave function ψ where the square of the amplitude of the wave function lψl2 gives the probability of finding the electron at a point. (No mathematical treatment is required.)
-
Show an understanding of the concept of a potential barrier and explain qualitatively the phenomenon of quantum tunnelling of an electron across such a barrier.
-
Describe the application of quantum tunnelling to the probing tip of a scanning tunnelling microscope(STM) and how this is used to obtain atomic-scale images of surfaces. (Details of the structure and operation of a scanning tunnelling microscope are not required.)
-
Apply the relationship transmission coefficient T = exp(-2kd) for the STM in related situations or to solve problems. (Recall of the equation is not required.)
-
Recall and use the relationship R + T = 1, where R is the reflection coefficient and T is the transmission coefficient, in related situations or to solve problems.