The purpose of these recommendations is to help students studying physics . The material presented in them is the basis for the study of disciplines of the professional cycle .. Questions are also brought to independent work on the theoretical material presented both for a deeper understanding of the physical side of the phenomena considered, and for strengthening the skills of applying the mathematical apparatus .. The recommendations meet educational standards and are intended for students enrolled in 110800. 62 Agroengineering, 140400. 62, Electricity and Electrical Engineering, 221700. 62 Standardization and Metrology, 022000. 62 Ecology and Nature Management, 110900. 62 Production and processing technology with /h products, 110400. 62 Agronomy, 111100. 62 Zootechnics .