  We use analogies to give introductory laboratory students intuition about
measurement uncertainties. Using a battery-resistor circuit we discuss
uncertainty concepts and derive expressions for uncertainty of the mean and
sums of uncertainties. Finally, we draw attention to the fact that the
interpretation of standard deviation as uncertainty depends on the statistical
distribution of the data, while the interpretation of uncertainty of the mean
is largely insensitive to such distribution, especially for large samples. If
the resistor in the battery-resistor circuit is a resistive loudspeaker, the
uncertainty or noise is literally the acoustic power of the sound produced by
such noise. In the sound analogy the statistical distribution of the noise is
related to its timbre.
