Can this also apply to digital electronics?

The equivalent resistance across the battery is 27 ohms. The total battery current is 0.37 A.

The terms "analog" and "digital" refer to how information is encoded to change the voltages and currents in a circuit.

In this circuit, there is no information going on, and nothing is changing. If you had an analog or digital circuit and you needed some reference voltages for it, the little piece of electronics in this picture could be used in either type.

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it