# Negative Effective Resistance

Assume that we have a circuit that is connected with components that have positive resistance. At this point the effective resistance between every two node is positive. (below is an example of such circuit) simulate this circuit – Schematic created using CircuitLab

Now, if we add components with negative resistance, we can have negative effective resistance between two nodes. (Here the effective resistance between node 1 and node 3, has become -2). simulate this circuit At this point, is it possible to make the effective resistance between every two nodes positive by adding more negative resistance components?

• "negative" resistance is not a real world phenomenon to my knowledge... Jun 17, 2016 at 21:05
• negative resistance does exist, see tunneling diodes, and it got Esaki a Nobel prize. it's relative to operating conditions. the posters question is not really clear Jun 17, 2016 at 21:20
• @vicatcu Even if you think it doesn't exist, think of it as an abstract element. @ b degnan, where is the ambiguity? Jun 17, 2016 at 21:31
• Please make this question clearer, potentially with a pseudo-circuit diagram. You can use the circuit diagram tool in the editor, and remember to use text labels liberally to refer to node points etc Jun 17, 2016 at 22:27
• Of course, negative resistances do exist - and are widely used in practice (filters, oscillators). There are various realization methods - but always on the basis of active componenets (transistors, opamps). Negative resistances are nothing else than voltage controlled current sources with the current going through the controlling voltage source.
– LvW
Jun 18, 2016 at 8:11