Units & Prefixes Flashcards

All 7 cards in this deck

Give the SI units of mass, force, energy and frequency.

Mass: kilogram (kg); force: newton (N); energy: joule (J); frequency: hertz (Hz).

What do the prefixes giga (G), mega (M) and kilo (k) multiply a unit by?

giga = $\times 10^{9}$, mega = $\times 10^{6}$, kilo = $\times 10^{3}$.

What do the prefixes centi (c), milli (m), micro (μ) and nano (n) multiply a unit by?

centi = $\times 10^{-2}$, milli = $\times 10^{-3}$, micro = $\times 10^{-6}$, nano = $\times 10^{-9}$.

True or false? J/kg is an acceptable unit for $g$, the acceleration due to gravity (gravitational field strength).

False. The alternative unit for $g$ is N/kg; J/kg is not the same as m/s$^2$.

How can you work out the unit of a quantity from an equation?

Rearrange the equation to make that quantity the subject, then replace every other quantity with its unit, e.g. $k = F/x$ gives N/m.

What is the SI unit of temperature?

The kelvin (K).

What is the resolution of a measuring instrument?

The smallest change in a quantity that the instrument can detect.