Write conventions the use of si unit
Answers
What are the rules (sign conventions) to use S.I units?
Answer
Hint: Here, we will proceed by mentioning the basic rules for writing the units for any physical quantity (which will include the sign conventions for S.I units too). We will also mention the rules for the symbols corresponding to these units.
Complete step-by-step answer:
The rules or sign conventions which are there to use or write S.I units for any quantity are given below:
1.1. Those units which are named after the name of scientists are always written with their first or initial letter being non-capitalized. This means that the starting letter of the S.I unit which is given after any scientist’s name should be a capital letter. For example: S.I unit of power is watt, S.I unit of inductance is henry and S.I unit of force is newton
2.2. The symbols used for the units which are named after the name of any scientist should be written by a capital letter. For example: symbol for power’s unit watt is W, symbol for inductance’s unit henry is H and symbol for force’s unit newton is N
3.3. The symbol of those units which are not derived from a proper name (i.e., not after the name of any scientist) are always given by non-capitalized letters. For example: symbol for the S.I unit of distance (i.e., metre) is m and the symbol for the S.I unit of mass (i.e., kilogram) is kg
4.4. Within or at the end of any symbol, no punctuation marks or any full stop should be used. For example: 50 metre is represented as 50 m not 50 m. (here, full stop is used at the end)
5.5. No plural form should be taken by the symbols of the units. For example: In order to represent 10 kilogram of rice, 10 kgs can never be used. Instead of this 10 kg is used
6.6. When the temperature is represented in Celsius scale, degree sign is always included but when the temperature is represented in Kelvin scale, then the degree sign should always be neglected. For example: temperature of 100 in Celsius scale is represented as 1000C0C whereas temperature of 273 in Kelvin scale is represented as 100 K.
7.7. In order to represent the division of one letter of the unit symbol by another letter of the unit symbol, use of solidus is fine. But if there occurs more than one division then the solidus should not be used. For example: S.I units of velocity can be represented as m/s or ms−1ms−1 and J/ K mol can be represented as JK−1mol−1JK−1mol−1 but cannot be represented as J/K/mol
8.8. There should always be left some space between the number (value of the quantity) and the symbol for the unit of that quantity. For example: 2.3 metre length is represented as 2.3 m
Note: Some other rules for writing units include that only the symbols which are accepted for any unit should be used. Not any short form of the whole unit will be entertained like the symbol corresponding to current’s unit (i.e., ampere) is A not amp, the symbol corresponding to time’s unit (i.e., second) is not sec.
Explanation:
Abbreviationa such as sec,cc,or mps are avoides and only standard unit symbols,prefix symbols,unit names,and prefix names are used