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Transitors are not passive why?

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walters

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Why do transitors need voltage to work?

Why are they active and not passive components?

Why do op-amps need voltage to work?

Diodes are passive so why does a transistor need voltage to work?
 

electronics_kumar

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answer for 1) and 3)
AS PER LAW OF CONSERVATION OF ENERGY ,energy cannot be created nor destroyed....if any device is called as a active means ultimately it should have a power supply so that law if conseravation of energy satisfies..

2) since it can amplify it can be called as active device
4)Diodes are passive so why does a transistor need voltage to work? i could not understand your question ..plz make it clear
 

yjkwon57

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Hi~~

Passive components such as resistors, capacitors, inductors, diodes, etc., have no control input. But, active components such as transistors, SCRs, TRIACs, etc., have control inputs for controlling the operating characteristics of their terminals.

Bye~~
 

brahma

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active devices are those which have the capability of amplifing input signals, passive components cannot do this moreover they dissipate power..
 

VSMVDD

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QUOTE:

AS PER LAW OF CONSERVATION OF ENERGY
,energy cannot be created nor destroyed....

what total rubbish


hahahahahahaahahahaha lol:))) makes me weep :cry:

so all this mass and darkmater dosnt exist becouse it was never created

however it hasnt been destroyed yet

ALL PARTICALES ARE ENERGY STRINGS

energy + energy = matter + energy

i think you live in a paradox


you can power any transistor from its own case
its the current it carries make's it an active component

forinstance a resistor is a passive componet
becouse it only passes a preset amount

whereas a transistor is an active component becouse it amplifies current
 

electronics_kumar

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what i am saying amplifier derives its energy from power supply for amplification.....law of conservation of energy is applicable...u check it
 

VSMVDD

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no its not

lossy law is the only law applicable to psu of voltage

lossy law is 75%25% for every 75% a system uses you get 25% matter 75% energy

so the law of conservation of energy dosnt work at quantum realm or below so is incredulious


it was proved years ago in too many ways

it has holes and flaws

in many realms

QUOTE:

what i am saying amplifier derives its energy from power supply for amplification.....law of conservation of energy is applicable...u check it





the perfect example of why you are wrong

pick a shell up on the beach listen to its tip

its an amplifier
where is its power supply ??? or energy input

it is already matter +{your holding it right}
this is where the energy came from it uses
you picked it up and transfered time to it

any equassion can be summed up to a shape that fits in a cube

from a sphere that fits inside this cube

you have the exact properties of the cube


a cube with a sphere inside it represents the law of conservation of energy

and dosnt have a golden circle ratio of 1:1 transfer


at some realms the cube will appear bigger than the sphere
{when its the bigger than you {higher order}}
but when its smaller or around the same size
as your perception it will appear that it fits in perfect { a paralax}{atomic platelet formation atomic cubic formation in xtals etc etc}

however the sphere always even thou it appears not to at some levels has a 25% less square area inside the cube it dosnt cover

this is a lossy system
where current is the cube voltage is the sphere and resistance is the pyramid

inside each other and the level {realm } is the order they fit together and in what proportions

BUT for the law of consrvation of energy to be fully transpective

every realm would need to be a cube or a sphere or a pyramid

and this contradicts the spherical laws of physics

and is infact what the universe tryes to do
all the time

becomes one or other ordered realm


at some levels it works most often it exibits loss


basicaly if the law of conservation of energy was nothing more than transparent

then each time a super nova went up the whole universe would also blow up

or colapse

or probably wouldnt have got started

it has been proved many ways that energy turns into information

informations is never lost

however it can become disordered


and this is loss ?? yes ... so...

Added after 47 minutes:

brahma said:
active devices are those which have the capability of amplifing input signals, passive components cannot do this moreover they dissipate power..


no digital logic stands in your way so does tristate

none of these devices are concidered passive
they are active component's

becouse they perform a higher order task addative
and not a lower order task of regression however this is made
in information terms only

a passive component always destroys or disorders info {phase shift added noise etc etc}

the problem is active compoenents are all made from passive ones

just sunk to a different level however performing the same task with less insertion loss to the system to the point where they have gain {addition}

add lots of gain together and man thats an amplifier of information order

from disorder you got from combining lots of ordered threads + system loss
 

electronics_kumar

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VSMVDD wrote

pick a shell up on the beach listen to its tip

its an amplifier
where is its power supply ??? or energy input


nice VSMVDD,ENERGY FOR THE SHELL COMES FROM THE AIR THAT IS FLOWING INTO IT...IF U ARE HOLDING OT PORPERLY TO GET MAX GUSH OF AIR THAN U WILL GET MORE SOUND I MEAN OUTPUT...


HOT DEBATE CONTINUES
 

evehits

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guys guys you drifted away that is not the answer
transistors need power supply to bias them as they cannot work without providing the correct amount of biasing voltage needed for that. so as for op amps which consist of transistors, diode, etc
now active devices are defind as those who can control the flow of charge through them. hence they require some kind of energy
for that, diodes are inbetween cos they control the flow of current in forward and reverse region. and passive as this control depends on the condition of the applied signal
cheers
 

VSMVDD

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electronics_kumar said:
VSMVDD wrote

pick a shell up on the beach listen to its tip

its an amplifier
where is its power supply ??? or energy input


nice VSMVDD,ENERGY FOR THE SHELL COMES FROM THE AIR THAT IS FLOWING INTO IT...IF U ARE HOLDING OT PORPERLY TO GET MAX GUSH OF AIR THAN U WILL GET MORE SOUND I MEAN OUTPUT...


HOT DEBATE CONTINUES


as the man says all amplifers need bias...

or they are open loop ... and you would be listening thru a scollop shell


as for the spiral shell ye its more of a filter than an amplifier
due to its regular size and smooth walls

however an antenna any bit of metal tuned right has gain
so any voltage flying around at the right frequency will start it resonating and it will sympothise
hence another exibit of an addative gain system from a passive element

adding weight to what i said

your right it does need an energy input

however the point i made stands

all energy is a measure of voltage even the wind and potential time relativity

WAKE UP!!!! the point is

it is still an amplifier {concentrator.....}

even if you stand in a cave
with no air flow.... try it !!!! youll just get the same relative output

or in a wind tunnel wont matter
becouse the amount of output is relative to several conditions not just air inrush

air inrush will add to desructive forces and cause noise in the amplified output

and that is relative to the place you are and what is going on in that place

two shells can be used to increase the gain but again youll increase noise

much likened to a lense and the sun two lenses concentrate better
however you can still start a fire with just one

both are concidered passive componenets of the planet
where as sentiant life is the active force....

the point is you dont have to have active components to amplify

you just have to have a system

that produces less passive effectors{destrcutive of info ordering } and exibits at least some addative effectors{addative to info ordering}

the debate goes on and on
however i enjoy a good topic

Added after 28 minutes:

evehits said:
guys guys you drifted away that is not the answer
transistors need power supply to bias them as they cannot work without providing the correct amount of biasing voltage needed for that. so as for op amps which consist of transistors, diode, etc
now active devices are defind as those who can control the flow of charge through them. hence they require some kind of energy
for that, diodes are inbetween cos they control the flow of current in forward and reverse region. and passive as this control depends on the condition of the applied signal
cheers

no transistors are a switch only

the bias is used to correct the input threshold levels to drive the device

into semi {biased} saturatory level

so you can pass a sine wave and not get distortion {clipping}

look above a transistor purly ampilifies current or voltage

but bias is just used to give it linearity

bias is therefore just another example of how passive components
are used to give you a cleaner {less info lossy} addative system
 

Naveed Alam

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Why do transitors need voltage to work?
to flow its free electrons (or holes)

Why are they active and not passive components?
b/c devices who need power to operate, are called active devices

Why do op-amps need voltage to work?
b/c it has transistors etc(active devices), as its integral part.

Diodes are passive so why does a transistor need voltage to work?
Diodes also need power to operate..
 

gunsuresh

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eventhogh transistor needs voltage to work, it generates barrier voltage without any bias. hence it comes under active device.
 

electronics_kumar

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gunsuresh said:
eventhogh transistor needs voltage to work, it generates barrier voltage without any bias. hence it comes under active device.
i think your justificatuion is not correct ..if it follows than diode is a active device which is wrong decision..we cen't decide in that way
 

xxargs

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electronics_kumar said:
gunsuresh said:
eventhogh transistor needs voltage to work, it generates barrier voltage without any bias. hence it comes under active device.
i think your justificatuion is not correct ..if it follows than diode is a active device which is wrong decision..we cen't decide in that way


Diod is active component depend of fixed controlling power flow ie. not symetric function on reverse polarity. IMHO.

You have also tunneling diode using in Microwave as amplifier (gain depend of negative resistance in very small region) , PIN-diodes to build adjustable attenuators in RF-circurits or cap-diodes for tuning oscillators etc. and I cannot call this as passive components...
 

vlsiattitude

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what i think is that active devices can channelize energy from power supply to signal which u waant to process. where as passive devices dont do that rather they take away energy from your signal
 

ferrite

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active component means it can amplify signal
 

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