文档介绍：Scientific English Writing Section Ⅳ
Ex. 2
II. 19. This rule can be used for all integers, both positive and negative.
27. Impedance in an ac circuit plays the same role that resistance does in a dc circuit.
28. Two parallel wires a distance of δ apart carry the current i.
II. 7. This facilitates their use in circuit analysis.
10. Here we must use wires one thousandth the diameter of a silk thread.
14. AC can be changed into DC, a process called rectification.
16. An instrument for measuring current, voltage and resistance, the multi-meter is widely used in the work having connection with electricity.
19. This curve shows the fall in conductivity with increasing temperature.
IV. 1. The second law of motion provides a method for measuring shat is called the “inertial mass” of a body. All one needs to do is to apply the same force in turn to a standard of mass and to an unknown mass and then pare their accelerations, something that can be done anywhere in the universe with the same results. No matter where we are, we can always tell a wooden ball from a lead ball of the same size by throwing them.
2. **: male, born in 1938, professor, and advisor for doctoral students. He graduated from the Xi’an Military munications Engineering Institute in 1964 and remained there as a faculty member. He has long been engaged in the teaching and research in the field of radar. Through close cooperation with quite a few radar research institutes and enterprises, he has essively undertaken or taken charge of more than twenty national defence key preliminary research projects and engineering projects with many practical achievements, most of which have been popularized and applied, or used to equip the armed forces, thus making contributions to the development of radar technology in China.
Independent work 3
1、人体是由大大小小无数结构构成的。(using an adjective phrase to express the underlined part)
2、这台计算机的速度由于它使用了继电器而受到了限制。(using a prepositional phrase to express the underlined part)
3、他