1. .1 The particles in the nucleus of an atom are
(A) Electron and Proton
(B) Electron and Neutron
(C) Proton and Neutron
(D) Only Neutron
2. .3 Controlling factor for primary emission is
(A) Speed of primary electrons
(B) Light energy
(C) Amount of heat
(D) None of these
3. .4 Controlling factor/s for secondary emission is
(A) Mass of primary electrons
(B) No. of primary electrons
(C) Speed of primary electrons
(D) All of these
4. .5 Controlling factor/s for photo emission is
(A) Light intensity
(B) Frequency of light
(C) Speed of light
(D) All of these
5. .7 No. of electrodes in diode valve/tube is/are
(A) 2
(B) 3
(C) 4
(D) 5
6. .8 No. of electrodes in triode valve/tube is/are
(A) 2
(B) 3
(C) 4
(D) 5
7. .9 No. of electrodes in tetrode valve/tube is/are
(A) 2
(B) 3
(C) 4
(D) 5
8. .10 No. of electrodes in pentode valve/tube is/are
(A) 2
(B) 3
(C) 4
(D) 5
9. .11 Number of electrons in outermost shell of semiconductor material is
(A) More than 4
(B) Always 4
(C) Less than 4
(D) 8
10. .12 Number of electrons in outermost shell of trivalent atoms is
(A) 3
(B) 4
(C) 5
(D) 6
11. .13 Number of electrons in outermost shell of pentavalent atoms is
(A) 3
(B) 4
(C) 5
(D) 6
12. .14 In N-type semiconductors majority charge carriers are
(A) Holes
(B) Electrons
(C) Neutrons
(D) Protons
13. .15 In P-type semiconductors majority charge carriers are
(A) Holes
(B) Electrons
(C) Neutrons
(D) Protons
14. .16 In N-type semiconductors minority charge carriers are
(A) Holes
(B) Electrons
(C) Neutrons
(D) Protons
15. .17 In P-type semiconductors minority charge carriers are
(A) Holes
(B) Electrons
(C) Neutrons
(D) Protons
16. .18 Resistance of semiconductors ------ with doping
(A) Increases
(B) Decreases
(C) No effect
(D) None of these
17. .19 Conductance of semiconductors ------ with doping
(A) Increases
(B) Decreases
(C) No effect
(D) None of these
18. .20 The forbidden energy gap of a semiconductor is
(A) Widest
(B) Narrower
(C) Overlap
(D) None of these