工程专业英语指南.ppt

Reading helps writing, listening and speaking Summarizing your reading in letter, note-making Using recorded information, matching opinions and texts Discussions, debates, appreciation Air conditioning may include the function of heating and ventilation but in addition is concerned with lowering the temperature of the thermal environment. Heating, ventilation and air conditioning may be defined in general terms as the control of the environment within enclosed space. T T Rooms are largely heated by convection currents. T T Because the winds transfer heat from warm to cool areas, the density and temperature difference tends to be equalized. T F The temperature of the air in the immediate vicinity of a radiator rises and so the air density changes. After a uniform temperature has been established, molecular collisions do not continue to transfer. Comprehension: 1. The radiation emitted by all bodies consists of electromagnetic waves of many frequencies A. except visible light. B B. from long infrared rays through visible light to short ultraviolet rays. C. Which are all in visible rays. 2. At ordinary temperatures A. Electrons in an object change energy states. C B. Electrons in an object change energy states for only a few times a second. C. Electrons in an object change energy states for millions of times a second. 3. Radiation depends on A. The materials composing the bodies. C B. The surroundings. C. The temperature. 4. If an object had no way to collect heat by itself, A. It would radiate its energy away and drop to a temperature of freezing-point. C B. It would absorb heat from other objects to keep its temperature. C. It would radiate its heat away and drop to a temperature of absolute zero. Words: mechanics n. 力学The branch of physics that is concerned with the analysis of the action of forces on matter or material systems.2. kinematics n. 运动学The branch of mechanics that studies the motion of a body or a system of bodies without consideration given