If you are given the following values that come directly or indirectly from measurements, what will you assume is the range of possible values that they represent?

Question

evolved · Answer

If you are given the following values that come directly or indirectly from measurements, what will you assume is the range of possible values that they represent?
a. 2.2 L (the volume of a basketball)
b. 3 μm (the diameter of a hair)
c. 2.0 × 10-6 nm (the diameter of a proton)
          d. 1.98 × 105 kg (the mass of a whale

mww · Answer

The smallest unit given (or last significant figure) is known as the precision.
The absolute error is given by half of the precision.
The range is the measurement +/- absolute error

So for 2.2L the tenth unit is the smallest unit, thus the precision is 0.1 (a tenth)
The abs. error is half of this so 0.5 x 0.1 = 0.05
So we add or subtract 0.05 from 2.2 to get a possible range of 2.15 - 2.25

Try finding the smallest unit for every case and the rest is simple.