1. Chapter 1 Measurement 第1章 測量

2. Chapter 1 Measurement 1-1 What is Physics? 1-2 Measuring Things
1-3 The International System of Units
1-4 Changing Units
1-5 Length
1-6 Time
1-7 Mass

3. 1-1 What is Physics?
Science and engineering are based on measurements and comparisons.
Global Positioning System (GPS)
全球定位系統

4. 1-2 Measuring Things
We measure each physical quantity in its own units, by comparison with a standard.
Base standards must be both accessible and invariable.

5. 1-2 Measuring Things standard 標準 unit 單位 base quantity 基本量
derived quantity 導出量
base unit 基本單位
derived unit 導出單位

7. SI Base Quantities length 長度 mass 質量 time 時間 electric current 電流
thermodynamic temperature 熱力學溫度
amount of substance 物質量
luminous intensity 發光強度

8. 1-3 The International System of Units
SI (Système International) 國際單位制
metric system 公制
scientific notation 科學記號、科學記法
3.56  109 m
4.92  107 s

10. 10進位倍數和分數符號 字首 符號 10的次方 名稱 yotta Y 1024 佑 deci d 10-1 分 zetta Z 1021 皆
centi c
10-2 釐
exa E
1018
艾(百萬兆)
milli m
10-3 毫
peta P
1015
拍(千兆)
micro
10-6 微
tera T
1012 兆
nano n
10-9
奈(毫微)
giga G
109
吉(十億)
pico p
10-12
皮(微微)
mega M
106 百萬
femto f
10-15
飛(毫微微)
kilo k
103 千
atto a
10-18
阿(微微微)
hecto h
102 百
zepto z
10-21 介
deka(deca) da
101 十
yocto y
10-24 攸

11. 1-4 Changing Units conversion factor 換算因子、換算因數 significant figure 有效數字
decimal place 小數位、小數位數

12. 1-5 Length
In 1792, Republic of France established a new system of weights and measures.
The unit of length, the meter, was defined as one ten-millionth of the distance from the north pole to the equator.
International Bureau of Weights and Measures 國際度量衡局
Standard meter bar
Platinum-Iridium bar

13. 1-5 Length
In 1960, the meter was defined to be wavelengths of a particular orange-red light emitted by krypton-86 in a gas discharge tube.
Krypton 氪
Gas discharge tube 氣體放電管

14. 1-5 Length
In 1983, the meter was defined as the length of the path traveled by light in a vacuum during a time interval of 1/ of a second.
The speed of light c is then exactly
c = m/s.

16. Standard 標準 Base standards must be both accessible and invariable.
primary standard 原級標準、原標準
secondary standard 次級標準、副標準
order of magnitude 數量級

17. 1-6 Time Time has two aspects Earth’s rotation Quartz clock 石英鐘
When did it happen?
What is its duration?
Earth’s rotation
Quartz clock 石英鐘
One second is the time taken by oscillations of the light emitted by a cesium-133 atom.
Atomic clock 原子鐘
National Institute of Standards and Technology (NIST) 國家標準與技術研究院

19. 10-hour watch

20. Variations in the length of the day over a 4-year period

21. 1-7 Mass Carbon-12 atom atomic mass unit, u 原子質量單位
1 u =  1027 kg
Density,  密度
liquefaction 液化
quicksand 流沙

22. The international 1 kg standard of mass (platinum-iridium)

24. Uncertainty 誤差 Accuracy 準確度 Precision 精密度、精確度
Accuracy refers to how close a measurement is to the true value.
Precision 精密度、精確度
Precision in a strict sense refers to the repeatability of the measurement using a given instrument.