一些笔记

1Friction makes the work put into a machine greater than the useful work accomplished by it.
2By power is meant the speed,or rate,of doing work.
3Our semiconductor industry came into being at the end of the 1950s.
4the voltage across the registor is measured in volts.
5substituting Eq7 into Eq8,we get a=b.
6work equals(is equal to) force multiplied by distance.
7this equipment has quite a few advantages all its own.
8By observing the effect of a new drug on the patients,we can see its efficiency of the cure.
9Icon is almost as good a conductor as aluminium.
10On being heated,the air in the bottle will expand.
11Air exerts pressure in every direction.
12The hotter the body,the more energy it radiates.
13The ability of some elements to give off radiations is referred to as radioactivity.
14To do all this,a sound knowledge of computer science is required.
15The voltage across this capacitor is a few hundredths of a volt.
16Of the first four chapters, Chapter 3 is the most important.
17it is necessary to find how long a time it takes to solve this equation.
18Medium-sized computers now perform as large computers not long ago.

有用的句型:
1 be of great help to
2 only one fifth what it is now
3 half the final output
4 four times thicker than
5 the difference between these two values is 13 parts in a million.
6 From its definition as the ratio of distance to time,
7
8