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Wave-particle duality (A-level only)

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Question 15
a.

In a transmission electron microscope (TEM), magnetic lenses are used to focus the electron beam. Which of the following best describes the function of the objective lens?

  • A. It produces and focuses a parallel electron beam onto the specimen surface.
  • B. It generates the high potential difference that accelerates electrons from the filament.
  • C. It focuses the electrons that have passed through the specimen to form the first, highly magnified intermediate image.
  • D. It casts the final magnified image onto a fluorescent screen, photographic plate, or CCD detector.
[1]
b.

In a particular TEM, the electrons are accelerated from rest through a potential difference of 18.0 kV18.0\text{ kV}18.0 kV. Relativistic effects are negligible at this accelerating voltage.

Suggest, with a calculation, whether a crystal lattice with a plane separation of 0.050 nm0.050\text{ nm}0.050 nm can, in principle, be resolved in this TEM.

[4]
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Wave-particle duality (A-level only) Questions

  1. A Level
  2. /Physics
  3. /Wave-particle duality (A-level only)

26 exam-style questions on AQA A Level Physics Wave-particle duality (A-level only), covering Newton's corpuscular theory of light (A-level only), Significance of Young's double slits experiment (A-level only), Electromagnetic waves (A-level only), The discovery of photoelectricity (A-level only), Wave-particle duality (A-level only), and Electron microscopes (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

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