Question

Which of the following representations of unit are correct?

• A. 1.6 kPa
• B. 55 m-s
• C. 10 kTg
• D. 23 joules

Answer 1

Answer: (A), (D)

The correct options are
A 1.6 kPa
D 23 joules

• No punctuation is allowed between the prefix and the unit. So, 55 m-s is wrong. 55 ms is the correct representation.
• Multiple prefixes are not allowed in units. So, 10 kTg is wrong. It should be 10 Pg or 10 peta grams.
• Prefix of a unit should be written in lower case letter from yocta (${10}^{-24}$) till kilo (${10}^3$). The first letter of the units named after a scientist should be capitalized. So, 1.6 kPa or 1.6 kilo pascals is correct.
• Plural is allowed in units written in full form but the first letter shouldn't be capitalized. So, 23 joules or 23 J is correct.