Answer Posted / thowsif_emerson_csm team
NPN Transistor :-
Just as in the case of the PN junction diode, the N
material comprising the two end sections of the NP N
transistor contains a number of free electrons, while the
center P section contains an excess number of holes. The
action at each junction between these sections is the same
as that previously described for the diode; that is,
depletion regions develop and the junction barrier appears.
To use the transistor as an amplifier, each of these
junctions must be modified by some external bias voltage.
PNP Transisitor:-The PNP transistor works essentially the
same as the NPN transistor. However, since the emitter,
base, and collector in the PNP transistor are made of
materials that are different from those used in the NPN
transistor, different current carriers flow in the PNP
unit. The majority current carriers in the PNP transistor
are holes. This is in contrast to the NPN transistor where
the majority current carriers are electrons. To support
this different type of current (hole flow), the bias
batteries are reversed for the PNP transistor.
| Is This Answer Correct ? | 14 Yes | 4 No |
Post New Answer View All Answers
why current is constant on d.c?
Sir,In our company there are 3 caterpillar make(capacity:(1) 3.3KV,2.5MW(2)3.3KV,2.5MW & (3)3.3KV,1.9MW) & 1 deutz make (capacity:11KV,3.8MW)gas engines utilised,all are running in paralell. There are three transformer utilised,(1) 6.25MVA,3.3KV/22KV,Impedence voltage:6.7% used for two generator,both are 2.5MW(2)5.5MVA,3.3KV/22KV,Impedence voltage:7.2% used for one generator of 2.5MW & (3) 5.5MVA,11KV/22KV,Impedence voltage:7.8% used for one generator of 2.5MW.all generator breakers capacity of 1250Amps. Sir,I want the details of fault level calculation of generator,transformer individually & for whole system. If you require any information from me.feel free for contact me sir.pl.send the answer of my question as the earliest as possible.
How to prepare electrical preventive maintenance plan & shedule of machine tools in manufacturing unit.
what is meant by surge? what we called for high currents?
A 10 MVA, 66KV, 50Hz, Y-connected 3-phase alternator has synchronous reactance of 0.635 Ù. It is working at full load at 0.8 lagging p.f. condition. Find torque angle, neglect armature resistance.
What is quadrantal symmetry?
Is there any standard guidelines/Criteria to design NGR/NGT.?
Draw the vector diagramme for Asynchronous Induction Generator at noload,half load and fullload.
please send me RRB electrical engineer previous year questions for Sr. Section Engineer
What is effect of harmonic current (Draw by VFD) on power system/ electrical Equipments ?
explain different types of d.c motors?
when will be the iocl interview results i faced interview on 8th september 2008 iam from electrical branch i faced interview for the post of electrical engineer??????????????????????//
Draw the line diagram of diffretial relay connected to transformer?
how copper and aluminium wires or cables are choose for current rating? please provide copper and aluminium wire selection chart for different current rating ?
Either It Possible a dc Motor to Run On Ac Drive [ Ex : ACS 800 , Yaskawa F7 ] If it is Possible How Pls Inform Me dinesh_elect_eng@yahoo.com
