I'll just explain few facts about analog computers (however you can find more on Wikipedia) :
1. It work on mathematical/ physical formulas (for example Ohms law)
2. It is really easy and helpful to create one.
3. It can calculate much faster than digital.
4. Reason why we are using digital instead of analog is because, it is really hard to get for example potentiometer or voltmeter with accuracy about 0,000000000001% to count high number equations like 10000000000 - 5456937.
My computer is simply working on voltage difference ( 30V - 20V = 10V)
This way u can easily subtract numbers.
- The orange line is the number from which we want to subtract.
(x - 20 = 10)
- The green one is the subtractor
(30 - x = 10)
- The blue line is the result.
(30 - 20 = x)
