% FILENAME = N10.TXT
% Safety
% Release version 2, January 2000

%Question: 1
#10.1 You can safely remove an unconscious person from contact with a high 
voltage source by: 

pulling an arm or a leg 

wrapping the person in a blanket and pulling to a safe area 

calling an electrician 

turning off the high voltage and then removing the person 

% ans 4 

%Question: 2
#10.2 For your safety, before checking a fault in a mains operated power supply 
unit, first: 

short the leads of the filter capacitor 

turn off the power and remove the power plug 

check the action of the capacitor bleeder resistance 

remove and check the fuse in the power supply 

% ans 2

%Question: 3
#10.3 Wires carrying high voltages in a transmitter should be well insulated to 
avoid: 

short circuits 

overheating 

over modulation 

SWR effects 

% ans 1

%Question: 4
#10.4 A residual current device is recommended for protection in a mains power 
circuit because it: 

reduces electrical interference from the circuit 

removes power to the circuit when the phase and neutral currents are not equal 

removes power to the circuit when the current in the phase wire equals the 
current in the earth wire 

limits the power provided to the circuit 

% ans 2

%Question: 5
#10.5 An earth wire should be connected to the metal chassis of a 
mains-operated power supply to ensure that if a fault develops, the chassis: 

does not develop a high voltage with respect to earth 

does not develop a high voltage with respect to the phase lead 

becomes a conductor to bleed away static charge 

provides a path to ground in case of lightning strikes 

% ans 1

%Question: 6
#10.6 The purpose of using three wires in the mains power cord and plug on 
amateur radio equipment is to: 

make it inconvenient to use 

prevent the chassis from becoming live in case of an internal short to the 
chassis 

prevent the plug from being reversed in the wall outlet 

prevent short circuits 

% ans 2

%Question: 7
#10.7 The correct colour coding for the phase wire in a flexible mains lead is: 

brown 

blue 

yellow and green 

white 

% ans 1

%Question: 8
#10.8 The correct colour coding for the neutral wire in a flexible mains lead 
is: 

brown 

blue 

yellow and green 

white 

% ans 2

%Question: 9 
#10.9 The correct colour coding for the earth wire in a flexible mains lead is: 

brown 

blue 

yellow and green 

white 

% ans 3

%Question: 10
#10.10 An isolating transformer is used to: 

ensure that faulty equipment connected to it will blow a fuse in the 
distribution board 

ensure that no voltage is developed between either output lead and ground 

ensure that no voltage is developed between the output leads 

step down the mains voltage to a safe value 

% ans 2