Hi,

Reference : http://www.allaboutcircuits.com/vol_1/chpt_2/6.html

With respect to explanation of linearity, it would be better if the scaling and additivity property are stated.
For example : Although y=mx+c, with c !=0 is mathematically a linear function, when it comes to circuit, if
an element has V = iR + k, k !=0, then it is not a linear element.

Linearity should also imply, no input = no output.


Regards,

 

For example : Although y=mx+c, with c !=0 is mathematically a linear function, when it comes to circuit, if
an element has V = iR + k, k !=0, then it is not a linear element.

Linearity should also imply, no input = no output.

I disagree with several aspects of those statements, if the graph is a straight line, it is linear. Crossing isn't part of the definition, though for a resistor it is the norm. There are many cases that solid state circuits are linear but not referenced to zero as part of the function.

Any function that can be plotted on a graph as a straight line is called a linear function. For circuits with stable resistances, the plot of current over voltage is linear (I=E/R).

I agree with this statement (part of the review at the end of the chapter).

Why not register? It is free and easy. We can discuss this in more detail. I've been wrong before, I am not the final arbiter.

 

Linearity should also imply, no input = no output.

A single supply op amp may have a linear response to an input, and yet have an output = 1/2 Vcc with no input.

If you want to pursue this issue, please register and post your concerns.