第291課: Measurements

The commonality that America has with Japan is that there are two competing systems of measurement with one being far more prevalent than the other. The majority of measurements that you will see in Japan will be in the universal metric system. However, there are situations in which native measure words are used instead. Rarer ones, as you can imagine, still live on in literature, set phrases, and other parts of life. 

This lesson's primary purpose is to show case these systems fully. Whether individual words are used or not will still be mentioned, but the entire lists will be given for those who wish to be pedantic.   

SI Units

 
Even if you are an American, the following terms should be very familiar to if you have studied the sciences. The only non-Western word below is 秒. However, there are times in Japanese when you do use セコンド・セカンド. These words are typically used in longer loan phrases.    
 
 English Quantity Japanese
 Meter Distance メートル
 Gram Mass グラム
 Second Time 秒
 Ampere Electric current アンペア
 Kelvin Heat ケルビン
 Candela Luminous intensity カンデラ
 Mole Amount モル
 
Expressing things like 時速 and 風速 complicate things. If you driving 60 km/h, you could certainly say 60キロメートル・パー・アワー. In practicality, just キロ could be used. This would be ambiguous with the actual distance you have traveled, but this is no different than in English. You could avoid English loans by saying 60キロ毎時間, but this is far from being colloquial. If you were dealing with seconds, you could use 秒, セコンド, or セカンド. / could be read as パー or 毎. However, if you choose 毎, you should use 秒. If you use パー, you should use セカンド・セカンド. What if you had m・s. If you see this, you would read it is as メートル、セカンド or メートル、セコンド.  
 
風速 is more difficult. The typical unit for this is m/s. This is read as メーター・パー・セカンド. A more technical reading of second in this field is セック. This comes from the English abbreviation sec. Now, because reading units (単位) is not universally standardized, the things mentioned above applies. For 風量 (air flow/volume), you have words like 立米 for m³. So m³/h = リュウベイ・パー・アワー. In actual application, you are to read things how your colleagues and or boss does. Because English and Japanese terms both exist for all of these things, this is only natural to happen.
 
The most important thing to not confuse is what is meant by average comments such as 風速50メートル and 時速50キロ(メートル). If you just get a number for any of these situations, you need to understand the base unit for these concepts. Thus, it should be a given that people are referred to m/s in regards to wind speed but km/h when referring to the speed of one's car. 


More Units

 面積 Area 長さ Length 重さ Weight 体積・容積 Volume/Capacity
 平方センチメートル cm2 ミリ[メートル] mm ミリグラム mg  立方センチメートル cm3
 平方メートル m2 センチ[メートル] cm グラム g 立方メートル m3
 平方キロメートル km2 メートル m キロ[グラム] kg ミリリットル ml
   キロ[メートル] km トン Ton シーシー cc
       リットル ℓ = Liter

Prefixes of Magnitude
 10-1 d Deci- デシ 101  da Deca- デカ 
 10−2 c Centi- センチ 102 h Hecto- ヘクト
 10−3 m Milli- ミリ 103  k Kilo- キロ
 10−6 μ Micro- マイクロ 106 M Mega- メガ
 10−9 n Nano- ナノ 109 G Giga- ギガ
 10−12 p Pico- ピコ 1012 T Tera- テラ
 10−15 f Femto- フェムト 1015 P Peta- ぺタ
 10−18 a Atto- アト 1018 E Exa- エクサ
 10−21 z Zepto- ゼプト 1021 Z Zetta- ゼタ
 10−24 y Yocto- ヨクト 1024 Y Yotta- ヨタ

 Derived Units

Unit Japanese Symbol Quantity 
 Hertzヘルツ Hz Frequency 
Radian ラジアン rad Angle 
Newton ニュートン Force 
Pascal パスカル Pa Pressure 
Joule ジュール Energy 
Volt ボルト Voltage 
Ohm  オーム ΩImpedance 
 Wattワット WPower 
 Coulomb クーロン C Electric charge
Farad ファラド Electric capacitance 
Lumen ルーメン lm Luminous flux 
Celsius セルシウス ℃ Temperature 
Siemens ジーメンス  S Electrical conductance
Tesla テスラ Strength of magnetic fields 
 Henry ヘンリー H Inductance
 Luxルクス lx Luminance 
Weber ウェーバ Wb Magnetic flux 
Sievert シーベルト Sv Equivalent dose 
Becquerel ベクレル Bq Radioactivity 
 Katal カタールkat
Catalytic activity 
 Grayグレイ Gy Absorbed dose 

Usage Note:  シーベルト and ベクレル have become frequently used in the news ever since the Fukushima Nuclear Power Plant Disaster in 2011.

English Quantity Japanese
 Meter Distance メートル
 Gram Mass グラム
 Second Time 秒(びょう)
 Ampere Electric current アンペア
 Kelvin Heat ケルビン
 Candela Luminous intensity
 カンデラ
 Mole Amount モル

 

Prefixes of Magnitude    

 10−1 d Deci- デシ 101 da Deca- デカ
 10−2 c Centi- センチ 102 h Hecto- ヘクト
 10−3 m Milli- ミリ 103 k Kilo- キロ
 10−6 μ Micro- マイクロ 106 M Mega- メガ
 10−9 n Nano- ナノ 109 G Giga- ギガ
 10−12 p Pico- ピコ 1012 T Tera- テラ
 10−15 f Femto- フェムト 1015 P Peta- ぺタ
 10−18 a Atto- アト 1018 E Exa- エクサ
 10−21 z Zepto- ゼプト 1021 Z Zetta- ゼタ
 10−24 y Yocto- ヨクト 1024 Y Yotta- ヨタ

Derived Units

 Unit Japanese Symbol Quantity
 Hertz ヘルツ Hz Frequency
 Radian ラジアン rad Angle
 Newton ニュートン N Force
 Pascal パスカル Pa Pressure
 Joule ジュール J Energy
 Volt ボルト V Voltage
 Ohm オーム Ω Impedance
 Watt ワット W Power
 Coulomb クーロン C Electric charge
 Farad ファラド F Electric capacitance
 Lumen ルーメン lm Luminous flux
 Celsius セルシウス °C Temperature
 Siemens ジーメンス S Electrical conductance
 Tesla テスラ T Strength of magnetic fields
 Henry ヘンリー H Inductance
 Lux ルクス lx Luminance
 Weber ウェーバ Wb Magnetic flux
 Sievert シーベルト Sv Equivalent dose
 Becquerel ベクレル Bq Radioactivity
 Katal カタール kat Catalytic activity
 Gray グレイ Gy Absorbed dose

Note:  シーベルト and ベクレル have become frequently used in the news ever since the Fukushima Nuclear Power Plant Disaster in 2011. 

 English Quantity Japanese
 Meter Distance メートル
 Gram Mass グラム
 Second Time 秒(びょう)
 Ampere Electric current アンペア
 Kelvin Heat ケルビン
 Candela Luminous intensity
 カンデラ
 Mole Amount モル

 

Prefixes of Magnitude    

 10−1 d Deci- デシ 101 da Deca- デカ
 10−2 c Centi- センチ 102 h Hecto- ヘクト
 10−3 m Milli- ミリ 103 k Kilo- キロ
 10−6 μ Micro- マイクロ 106 M Mega- メガ
 10−9 n Nano- ナノ 109 G Giga- ギガ
 10−12 p Pico- ピコ 1012 T Tera- テラ
 10−15 f Femto- フェムト 1015 P Peta- ぺタ
 10−18 a Atto- アト 1018 E Exa- エクサ
 10−21 z Zepto- ゼプト 1021 Z Zetta- ゼタ
 10−24 y Yocto- ヨクト 1024 Y Yotta- ヨタ

Derived Units

 Unit Japanese Symbol Quantity
 Hertz ヘルツ Hz Frequency
 Radian ラジアン rad Angle
 Newton ニュートン N Force
 Pascal パスカル Pa Pressure
 Joule ジュール J Energy
 Volt ボルト V Voltage
 Ohm オーム Ω Impedance
 Watt ワット W Power
 Coulomb クーロン C Electric charge
 Farad ファラド F Electric capacitance
 Lumen ルーメン lm Luminous flux
 Celsius セルシウス °C Temperature
 Siemens ジーメンス S Electrical conductance
 Tesla テスラ T Strength of magnetic fields
 Henry ヘンリー H Inductance
 Lux ルクス lx Luminance
 Weber ウェーバ Wb Magnetic flux
 Sievert シーベルト Sv Equivalent dose
 Becquerel ベクレル Bq Radioactivity
 Katal カタール kat Catalytic activity
 Gray グレイ Gy Absorbed dose

Note:  シーベルト and ベクレル have become frequently used in the news ever since the Fukushima Nuclear Power Plant Disaster in 201

Japanese Units

Before the advent of standardized units, the Japanese used a system of units called the 尺貫法. Remember that these are all 助数詞 (counters)!


Length: The

     The 尺 is the basis of the 尺貫法. The 曲尺 was used in carpentry, the 鯨尺 (25% larger than the 曲尺) in clothing, and the 呉服尺 (1.2x larger) in Japanese traditional dress.

 Unit Reading 尺 Equivalent Meters
 毛 もう 1/10,000 .00003030
 厘 りん 1/1,000 .0003030
 分 ぶ 1/100 .003030
 寸 すん 1/10 .03030
 尺 しゃく 1 .3030
 間 けん 6 1.818
 広 ひろ 6 1.818
 丈 じょう 10 3.030
 町 ちょう 360 109.1
 里 り 12,960 3297

Word Notes:

1. 広 is used for depth.

2. 里 previously stood for 600 meters.

Idiom Note: 一寸先は闇, literally "an inch ahead is darkness" is equivalent to "Who knows what tomorrow will bring?".  


Area: The

 Unit Reading 坪 Equivalent Square Meters
 勺 しゃく 1/100 .03306
 合 ごう 1/10 .3306
 畳 じょう 1/2 1.653
 坪 つぼ 1 3.306
 歩 ぶ 1 3.306
 畝 せ 30 99.17
 段・反 たん・ 300 991.17
 町 ちょう 3000 9917
 方里 ほうり 1555.2 15423

Word Notes:

1. The 歩 is used in agriculture whereas the 坪 is used in construction. For units larger than 1, they are used for large areas such as forests.

2. 歩 is often added to 畝, 反, and 町 when reading out measurements. For example, 6反8畝歩.  


Volume: The

 Unit Reading 升 Equivalent Liters
 才 さい 1/1000 .001804
 勺 しゃく 1/100 .01804
 合 ごう 1/10 .1804
 升 しょう 1 1.804
 斗 と 10 18.04
 石 こく 100 180.4

Mass: The 匁
 
 Unit Reading 匁 Equivalent Grams
 分 ぶ 1/10 .375
 匁・文目 もんめ 1 3.75
 百目 ひゃくめ 100 375
 斤(目) きん(め) 160 600
 貫(目) かん(め) 1000 3750

1. 氷を五十八貫目使ったわ、うちのねえさんにずいぶん厄介かけたわ。
     I used 58 kanme of ice. I sure put a lot of trouble on my sister. 
From 童謡 by 川端康成.