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if VxI on first and third quadrant ,power will dissipated for 2 and 4 quadrant power will be consumption
first and third quadrant ----->P=VxI or -Vx-I(nothing but VI)..leads to positive power will be released...doide belongs to this category
SECOND and foruth quadrant ----->P=-VxI or Vx-I...power will be consumed
It depends on what type of a diode you mean.
In most cases (rectifier, Zener, etc.) a diode is, no doubt, a PASSIVE device. Only in some special cases like with a tunnel diode, when its negative resistance region is used, it can be considered as an ACTIVE device.
"an activity" vs. "a passivity" of a device is exactly defined although the exact math evidence for a concrete device is not so easy. E.g. the activity of a linear N-port is determined by some particular properties of its immitance matrix (immitance = either impedance or admitance; so immitance matrices are Y, Z, H or G)
see also: Guillemin, E.A., Synthesis of Passive Networks, John Wiley & Sons, 1957
passive devices only dissipate a power from an external source,
active devices have an ability of amplifying a signal at one port of the device and deliver it to another port of it, where a load is connected, ie. they have some power gain > 1 (power itself is taken from a power supply, of course)
Any non-linear device can be considered to be an active device, in that it is capable of providing incremental power gain. Of course, the power gain can only occur in the incremental (small signal) sense.
If the i-v characterisitics of the diode are in region I and III, then it is a passive device (always dissipating power). I think most diodes fall into this category. Even in rectifiers, they are definitely not being used to amplify because they either are dissipating power (forward bias) or little power (reverse bias).
When I think of active devices, I usually, think of transistors that we can control by external stimulus (like a base current in a BJT or gate-source voltage in a FET).
All known devices are global passive because they dissipate power. If you bias a device at some operating point and consider only the signal derivation from this point you can amplify signal. So ouput signal power is greater than input power as in the case of bipolar transistor or MOS. Or the device could generate signal power. That is the case for a tunnel diode around the operating point. So active seems to apply for devices which could generate or amplify signal power but must spend DC power for that.
Active device: Needs power to work
Passive device: Does not power to work.
Take Transistor. You have to amplify a signal. Consider an input signal with a very small power (negligible). So if you want to amplify that signal to a very high magnitude you need power. You get that power from the supply voltage from the battery (usually denoted as Vcc).
Output power of the signal/ Input power of the signal can be >1 ( You should note that you get that additional power from the battery source).
Passive devices on the other hand won't amplify anything. They may give you impedence. They will never give you power. So they don't need power to operate.
Output power of the signal/ Input power of the signal can never be greater than 1. ( As energy is dissipated in the form of heat in passive devices, Power gain will never be equal to 1)
Coming to diode. I am a bit confused though. I would say that a normal diode is a passive device. I am not sure. I think if you consider two or more diodes together it is indeed possible to make it an active device. For eg: Consider transistors which are made of diodes. So it can also come under active device.