1) Question: Is a transistor really an amplifying element? Is it an active or passive device? Are there amplifying elements? Is it possible to amplify energy at all?
It is commonly known that the transistor serves as an active element used to construct amplifiers. However, I believe this notion is incorrect. The transistor is not an active but a passive element because it dissipates energy. Consequently, it acts as an attenuating rather than an amplifying element. Essentially, the transistor is a resistor (non-linear and electrically controlled, yet still a resistor) that reduces current flow.
True amplification is not possible; therefore, real amplifiers do not exist. The so-called "amplification" is merely an illusion, a clever trick, and the "amplifier" is nothing more than a "magic box." In this box, we observe a larger output power, but this is not the amplified small input power; it is something else's power (transformed DC power).
In analog electronics, we achieve this apparent "amplification" in what may be the most paradoxical, absurd, and silly manner to produce an output power greater than the input, we tap into a large power source and then discard part of it (ranging from zero to the entire power). In contrast, in energy systems, such wasteful practices are not feasible.
Is this correct?
Good Answer:
If one uses a small external magnetic field to excite a ferromagnetic material, it is possible to produce magnetic fields up to 10,000 times stronger within the material itself. This principle forms the basis for all transformers, as we rely on or exploit the high induction available within the material.
In this context, we are not amplifying anything but rather exploiting or controlling the material properties. If we were to do the same with wood, nothing would happen. Similarly, in smart manufacturing techniques, we have studied, designed, and used methods that allow semiconductors to exhibit similar properties. This enables us to utilize smaller amounts of power/energy to control large amounts of power/energy flow through the device itself. We can also apply this principle to hydraulic systems.
Where would this additional power come from? From inside the device? This is impossible, as you rightly pointed out. However, if we attach an external power source, we can use the transistor to control the flow of power through itself (not from within itself). Furthermore, through smart design and manufacturing techniques, we only need small amounts of power to control the flow of substantially larger amounts of power through the device.
Thus the use of the term amplification as the ability to control the flow of power and its use as the ability to generate power are not the same as the latter defies the laws of physics.The additional output power actually comes from the DC source in the biasing circuits.
The illusion, as mentioned above, is that it appears as if the device amplifies power from within itself. In reality, it only controls the flow of power through itself. As for passive and active devices, an active device is defined as one in which the flow of power can be controlled. Therefore, a resistor is considered passive, while a transistor is classified as active.
Thus, a transistor, as an active element, can be used to control the flow of substantially larger amounts of power through itself and, in doing so, allow amplification of the control signal. An example of this is the amplifier used for a radio.
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