% FILENAME = N11.TXT
% Semiconductors 
% Release version 2, January 2000
% Q 11 modified 6 Mar 2012

%Question: 1
#11.1 The basic semiconductor amplifying device is a: 

diode 

transistor 

pn-junction 

silicon gate 

% ans 2

%Question: 2
#11.2 Zener diodes are normally used as: 

RF detectors 

AF detectors 

current regulators 

voltage regulators 

% ans 4

%Question: 3
#11.3 The voltage drop across a germanium signal diode when conducting is 
about: 

0.3V 

0.6V 

0.7V 

1.3V 

% ans 1

%Question: 4
#11.4 A bipolar transistor has three terminals named: 

base, emitter and drain 

collector, base and source 

emitter, base and collector

drain, source and gate 

% ans 3

%Question: 5
#11.5 The three leads from a PNP transistor are named the: 

collector, source, drain 

gate, source, drain 

drain, base, source 

collector, emitter, base 

% ans 4

%Question: 6
#11.6 A low-level signal is applied to a transistor circuit input and a 
higher-level signal is present at the output. This effect is known as: 

amplification 

detection 

modulation 

rectification 

% ans 1

%Question: 7
#11.7 The type of rectifier diode in almost exclusive use in power supplies is: 

lithium 

germanium 

silicon 

copper-oxide 

% ans 3

%Question: 8
#11.8 One important application for diodes is recovering information from 
transmitted signals. This is referred to as: 

biasing 

rejuvenation 

ionisation 

demodulation 

% ans 4

%Question: 9
#11.9 In a forward biased pn junction, the electrons: 

flow from p to n 

flow from n to p 

remain in the n region 

remain in the p region 

% ans 2

%Question: 10
#11.10 The following material is considered to be a semiconductor: 

copper 

sulphur 

silicon 

tantalum 

% ans 3

%Question: 11
#11.11 A varactor diode acts like a variable: 

resistor 

voltage regulator 

capacitor 

inductor 

% ans 3

%Question: 12
#11.12 A semiconductor is said to be doped when small quantities of the 
following are added: 

electrons 

protons 

ions 

impurities 

% ans 4

%Question: 13
#11.13 The connections to a semiconductor diode are known as: 

cathode and drain 

anode and cathode 

gate and source 

collector and base 

% ans 2

%Question: 14
#11.14 Bipolar transistors usually have: 

4 connecting leads 

3 connecting leads 

2 connecting leads 

1 connecting lead 

% ans 2

%Question: 15
#11.15 A semiconductor is described as a "general purpose audio NPN device". 
This is a: 

triode 

silicon diode 

bipolar transistor 

field effect transistor 

% ans 3

%Question: 16
#11.16 Two basic types of bipolar transistors are: 

p-channel and n-channel types 

NPN and PNP types 

diode and triode types 

varicap and zener types 

% ans 2

%Question: 17
#11.17 A transistor can be destroyed in a circuit by: 

excessive light 

excessive heat 

saturation 

cut-off 

% ans 2

%Question: 18
#11.18 To bias a transistor to cut-off, the base must be: 

at the collector potential 

at the emitter potential 

mid-way between collector and emitter potentials 

mid-way between the collector and the supply potentials 

% ans 2

%Question: 19
#11.19 Two basic types of field effect transistors are: 

n-channel and p-channel 

NPN and PNP 

germanium and silicon 

inductive and capacitive 

% ans 1

%Question: 20
#11.20 A semiconductor with leads labelled gate, drain and source, is best 
described as a: 

bipolar transistor 

silicon diode 

gated transistor 

field-effect transistor 

% ans 4