1 )
When a hydrogen atom is raised from the ground state to an excited state , so .
. . . . . . . .
A ) P.E decreases and K.E increases ,
B ) P.E increases and K.E decreases ,
C ) P.E and K.E both are equal ,
D ) None of these ,
Correct
Answer : - B ) P.E increases and K.E decreases ,
2 )
The process by which the potential barrier of the depletion region can be
increased or decreased is called . . . .
. . . . . . . . . . ,
A ) biasing , B
) modulation ,
C ) doping , D
) None of these ,
Correct
Answer : - A ) biasing ,
3
) The process of combining low frequency
signals with high frequency carriers is called
……………….. ,
A ) amplification , B
) modulation ,
C ) rectification , D
) None of these ,
Correct
Answer : - B ) modulation ,
4 )
The minimum energy required to remove an electron from the metal surface is
called work function of metal .
5 )
The total energy of H - atom in ground state is . . . . . . . . . . . . ( -13.6 ev ) .
6 )
A laser device produces amplification in the . . . . . . . . . . . . . ( U.V or visible region of spectrum ) .
7 )
Thermodynamic scale or absolute scale is a temperature scale which is . . . . .
. . . . . . . . . ( independent ) of the nature of working substance .
8
) ( Metastable state ) . . . . . . . . .
. . . of atom or nucleus is a state that has longer life time than ordinary excited state .
