International System of Units (SI Units) or MKS units for seven base quantities of measurements and their derived quantities are unified. Specific symbols are designated for all. Only symbols can be used or written in full spells for these units of measurement, for example, there are 30 s or 30 seconds in half a minute. Not 30 sec.
Note 1: Units are always written and read as singular. We can not write 30 seconds, yes it is 30 seconds.
Note 2: Always give one space after numbers and symbols. Example 35 s is correct. 35s is not correct.
Let us quickly see how to present the symbols of various units:
1. Time: symbol (s). Read as a second. It is small s . Writing 10 s and 10 Second is correct. Use of 10 Sec. or 10 SEC. Or 10 seconds is not correct.
2. Mass: symbol (kg). Read as Kilo Gram. It is small k and small g. Writing 25 kg or 25 Kilo Gram is correct. The use of 10 KG or10 KGM or 10 KGS is not correct.
3. Length: symbol (m). It is small m. Writing 20 m or 20 Metres is correct. Note the spellings Metre is for measurement of length and meter is used for some indicating devices. Writing 20 Mtrs. or 20 Mt. or MTRs is not correct.
4. Temperature: symbol (K). Read as Kelvin. It is capital K. Kelvin is a base unit. Temperature’s popular conventional units for daily use are Degree Celsius and Degree Fahrenheit. Writing a temperature of 340 K or 240 Kelvin is correct. 240 °C and 240 °F (small symbol of degree ‘°’ appeared before C and F but not a symbol of degree is used when presented the temperature in Kelvin).
Note: 240 K and 240 °C and 240 °F are not the same values. There are certain conversion formulae for finding equivalent temperatures given on one scale to the others.
5. Current: symbol (A). Read as Ampere. It is capital A. Ampere is used for both alternate and direct current measurements. Writing 10 A or 10 Ampere is correct. 10 Amp. and 10 Amps. is not correct.
