CMS SI Units & Prefixes 2 — Questions and Answers
Question 1: The prefix 'centi-' equals which power of ten?
- 10⁻¹
- 10⁻² (Correct answer)
- 10⁻³
- 10⁻⁶
Correct answer: 10⁻²
Centi- means 10⁻², so one centimeter is one-hundredth of a meter.
Question 2: Which SI unit measures the amount of substance?
- Kilogram
- Mole (Correct answer)
- Candela
- Becquerel
Correct answer: Mole
The mole (mol) is the SI base unit for amount of substance, defined relative to Avogadro's number.
Question 3: What does the SI prefix 'mega-' represent?
- 10³
- 10⁶ (Correct answer)
- 10⁹
- 10¹²
Correct answer: 10⁶
Mega- represents 10⁶, meaning one million, as in megabytes or megahertz.
Question 4: The pascal (Pa) is the SI derived unit for:
- Energy
- Power
- Pressure (Correct answer)
- Force
Correct answer: Pressure
The pascal measures pressure, defined as one newton per square meter (N/m²).
Question 5: Which SI prefix is abbreviated with a lowercase 'u' in ASCII contexts?
- Milli
- Micro (Correct answer)
- Nano
- Pico
Correct answer: Micro
Micro (µ) is represented as 'u' in ASCII because the Greek letter µ is unavailable on some systems.
Question 6: The SI unit of frequency is the hertz (Hz), which equals:
- Cycles per minute
- Cycles per second (Correct answer)
- Radians per second
- Oscillations per hour
Correct answer: Cycles per second
One hertz equals one cycle per second, named after physicist Heinrich Hertz.
CMS SI Units & Prefixes 2
The prefix 'centi-' equals which power of ten?