B 1. The dilemma of modern techniques: Easy to achieve, difficult to understand
An example from a neighbored place, common to us: the thermometer. Familiar to us, that 'real' thermometer invented by Galilei and Torricelli 400 years ago, many times improved, but unaltered by his function. Easy to understand: all blows up by heat, different by its kind. Experiments on that can (and should!) be easily performed at the home table, not only in the physics classroom. Even the reason can be understood if we imagine (and partly can observe) the fact of the restless thermal movement of the smallest parts of material.
move on