Different value between calculation and experiment

[Azekzk]

Why when we do the experiment their value is not same with what we calculate that. For example the value of current when do the experiment not same with the calculated value. Can u give me ur opinion?

 

[LvW]

Why when we do the experiment their value is not same with what we calculate that. For example the value of current when do the experiment not same with the calculated value. Can u give me ur opinion?

Yes, I can. The (technical) world is real rather than ideal. That means, no part and no circuitry meets the desired value with an accuracy of 100%.
Example: If you try to design a resistive voltage divider (wanted and calculated ratio of 2:1) you never will meet this goal exactly.
More than that, most of the formulas in analog electronics (if not all) are only a simplification neglecting parasitic or other minor effects. Think of Ohm`s law: Is the current always proportional to the applied voltage? Only if you disregard the heating of the resistor.

 

[Azekzk]

Whats mean of ''simplification neglecting parasitic or other minor effects''. an u explain for more detail.

 

[LvW]

Whats mean of ''simplification neglecting parasitic or other minor effects''. an u explain for more detail.

* each capacitor and each coil has (neglected) losses
* each resistor has a tempertaure dependence and - at higher frequencies - causes some phase shift (capacitive/inductive effects)
* all common transistor formulas are approximations (neglecting leakage currents and non-linearities)
* all common opamp formulas neglect input/output resistances
* signals are called "sinusoidal" although they are not (THD with finite value)
* ..................

 

[Azekzk]

tq for ur help..