01․ Secondary breakdown occures in
Secondary breakdown caused by a localized thermal runway, resulting from high current consideration. In case of BJT, the base current is sufficiently high in saturation region so that the collector - emitter voltage is low. Thus current is increased due to lower collector - emitter voltage. Hence secondary breakdown is occured in BJT.
02․ Common emitter current gain hFE of a BJT is
Common emitter current gain is defined by the ratio collector current and the base current.
03․ The per unit impedance of a synchorous machine is 0.242. If base voltage is increased by 1.1 times, then per unit value will be
[math] Base \; impedance \; = rac{(KV)^2}{(MVA)} [/math]
[math] Z_{pu2} = Z_{pu1} rac{(KV_1)^2}{(KV_2)^2} = 0.242( rac{1}{1/10}^2 = 0.200[/math].04․ When the pn junction is forward biased the sequence of events that take place are
Under construction.
05․ The depletion region of a pn junction is one, that is depleted of
Under construction.
06․ The depletion region with in a pn junction is reduced when the junction has :
Under construction.
07․ A silicon pn junction in forward condition has a voltage drop closer to
Under construction.
08․ For a reverse biased pn junction, the electric current through the junction increases abruptly at
Under construction.
09․ The reverse saturation electric current of a pn junction varies with temperature (T) as
Under construction.
10․ The transition capacitance of a reverse biased pn junction having uniform doping on both sides, varies with junction voltage ( VB ) as
Under construction.
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