How much does lumped element model effect our analysis?

[Avichal]

Previously I never noticed that we are making this abstraction - to abstract continuous systems into an idealized discrete element like resistor or capacitor.

So since we have made this approximation, what kind of errors can occur in our calculations? Does this approximation ever fail so that our calculations just deviate away from the real thing?

 

[mfb]

All models have some limits.

Resistors behave differently if you measure their voltage very precise (it will fluctuate due to its temperature), apply a high current (it will increase its temperature and change its resistance), apply an even higher current (it can melt), use a high frequency and so on. Similar effects can happen in other elements of circuits (including cables) as well.