Question 24-26

Summary: Q24. Describe one way in which an understanding of crystal structure has impacted on science. Outline the methods of X-ray diffraction used by the Braggs to determine the structure of crystals. Q25. Graph the results of measurements of frequency of incident radiation and photoelectron energy taken in an experiment on the photoelectric effect, including the line of best fit. Explain how the reliability of the experiment could be improved. Q26. In the context of semiconductors, explain the concept of electrons and holes.