(a)[3]
the resistance of a metal at room temperature increases steadily with temperature,
(b)[4]
the resistance, at constant temperature, of a light-dependent resistor (LDR) falls as light intensity increases.
Physics 9702 · AS & A Level · Energy levels in atoms and line spectra
Energy levels in atoms and line spectra — practice question
Fig. 11.1 shows some electron energy bands in a solid. The width of the forbidden band, together with the number density of charge carriers in each band, depends on the type of solid. Use band theory to explain why
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