Term
1.1.2 State the ranges of magnitude of distances, masses and times that occur in the universe, from smallest to greatest. 

Definition
Distances: from 10–15 m to 10+25 m (subnuclear particles to extent of the visible universe). Masses: from 10–30 kg to 10+50 kg (electron to mass of the universe). Times: from 10–23 s to 10+18 s (passage of light across a nucleus to the age of the universe). 


Term
1.1.3 State ratios of quantities as differences of orders of magnitude. 

Definition


Term
1.2.1 State the fundamental units in the SIsystem. 

Definition
Students need to know the following: kilogram, metre, second, ampere, mole and kelvin. 


Term
1.2.4 State units in the accepted SI format. 

Definition
Students should use m s–2 not m/s2 and m s–1 not m/s. 


Term
1.2.5 State values in scientific notation and in multiples of units with appropriate prefixes. 

Definition
For example, use nanoseconds or gigajoules. 


Term
1.2.10 State uncertainties as absolute, fractional and percentage uncertainties. 

Definition


Term
1.2.13 State random uncertainty as an uncertainty range (±) and represent it graphically as an “error bar”. 

Definition
Error bars need be considered only when the uncertainty in one or both of the plotted quantities is significant. Error bars will not be expected for trigonometric or logarithmic functions. 

