Editing Analog computer (section)

==Components==
{{Unreferenced section|date=March 2013}}
[[File:NewmarkAnalogueComputer.jpg|thumb|A 1960 Newmark analogue computer, made up of five units. This computer was used to solve [[differential equation]]s and is currently housed at the [[Cambridge Museum of Technology]].]]

Analog computers often have a complicated framework, but they have, at their core, a set of key components that perform the calculations. The operator manipulates these through the computer's framework.

Key hydraulic components might include pipes, valves and containers.

Key mechanical components might include rotating shafts for carrying data within the computer, [[miter gear]] [[differential (mechanical device)|differentials]], disc/ball/roller integrators, [[Cam (mechanism)|cams]] (2-D and 3-D), mechanical resolvers and multipliers, and torque servos.

Key electrical/electronic components might include:
* precision resistors and capacitors
* [[operational amplifier]]s
* [[analog multiplier|multipliers]]
* [[potentiometer]]s
* fixed-[[function generator]]s

The core mathematical operations used in an electric analog computer are:
* [[addition]]
* [[integral|integration]] with respect to time
* [[additive inverse|inversion]]
* [[multiplication]]
* [[exponentiation]]
* [[logarithm]]
* [[division (mathematics)|division]]

In some analog computer designs, multiplication is much preferred to division. Division is carried out with a multiplier in the feedback path of an Operational Amplifier.

Differentiation with respect to time is not frequently used, and in practice is avoided by redefining the problem when possible. It corresponds in the frequency domain to a high-pass filter, which means that high-frequency noise is amplified; differentiation also risks instability.