Half-life of a radioactive substance is 20 min. The time between 20% and 80% decay will be
20 min
30 min
40 min
25 min
In a n-type semiconductor, which of the following statement is true ?
Electrons are majority carriers and trivalent atoms are dopants
Electrons are minority carriers and pentavalent atoms are dopants
Holes are minority carriers and pentavalent atoms are dopants
Holes are majority carriers and trivalent atoms are dopants
In a common emitter (CE) amplifier having a voltage gain G, the transistor used has transconductance 0.03 mho and current gain 25. If the above transistor is replaced with another one with transconductance 0.02 mho and current gain 20, the voltage gain will
1.5 G
The output Y ofthe logic circuit given below is
B.
By absorption laws
In the bandgap between valence band and conduction band in a material is 5.0 eV, then the material is
semiconductor
good conductor
superconductor
insulator
In a transistor output characteristics commonly used in common emitter configuration, the base current IB, the collector current lC and the collector emitter voltage VCE have values of the following orders of magnitude in the active region
IB and IC both are in µA and VCE in volt
IB is in µA and IC is in mA and VCE in volt
IB is in mA and IC is in µA and VCE in volt
IB is in mA and IC is in mA and VCE in mV