MCQ 1 If a worker has suffered from electric shock, he should be

(A) kept warm and covered (B) given an alcoholic drink (C) given a cold drink (D) made to walk

MCQ 2 Which one of the following is a temporary joint

(A) Welded joint (B) Press fit joint (C) Soldered joint (D) Riveted joint

MCQ 3 Which type of fire extinguisher is used in a welding shop

(A) Halon extinguisher (B) Foam type extinguisher (C) Dry powder extinguisher (D) Carbon Dioxide extinguisher

MCQ 4 The arc utilized in electric arc welding is a

(A) High voltage, high current discharge (B) Low voltage, low current discharge (C) Low voltage, high current discharge (D) High voltage, low current discharge

MCQ 5 Which one of the following is the type of transformer used in arc welding

(A) Step down (B) Step up (C) One-to-one (D) Capable of increasing supply voltage

MCQ 6 The welding machine, which is used to convert AC welding supply to DC welding supply is

(A) Engine generator set (B) Welding transformer (C) Rectifier set (D) Motor generator set

MCQ 7 In DC welding heat distribution is possible between electrode and the base metal due to the change of polarity. The distribution of heat is

(A) Positive 2/3 and negative 1/3 (B) Positive 1/3 and negative 2/3 (C) Positive 3/4 and negative 1/4 (D) Positive 1/4 and negative 3/4

MCQ 8 The size of a welding machine is determined by

(A) Open circuit voltage (B) Closed circuit voltage (C) Output amperage (D) Input amperage

MCQ 9 The position in which it is easiest to weld is

(A) Horizontal (B) Overhead (C) Vertical (D) Flat

MCQ 10 The electrode size refers to

(A) diameter of its core wire (B) thickness of flux coating (C) diameter (overall) of electrode (D) length of electrode

MCQ 11 One of the functions of electrode coating is

(A) to prevent rusting (B) to stabilize the arc (C) to increase welding current (D) to control arc temperature

MCQ 12 The electrodes are manufactured in two standard lengths namely

(A) 400 mm and 500 mm (B) 350 mm and 450 mm (C) 350 mm and 250 mm (D) 12” and 10”

MCQ 13 The correct colours for oxygen and acetylene hoses are

(A) Black for oxygen and red for acetylene (B) Black for oxygen and maroon for acetylene (C) Red for oxygen and blue for acetylene (D) Red for oxygen and maroon for acetylene

MCQ 14 In an acetylene cylinder, the acetylene is dissolved in

(A) Mercury (B) Carbon dioxide (C) Water (D) Acetone

MCQ 15 The function of the central hole in the tip of the cutting blowpipe is

(A) Supply acetylene for preheating (B) Supply oxygen for preheating (C) Supply acetylene for cutting (D) Supply oxygen for cutting

MCQ 16 Which fuel gas is used for cutting deep under water

(A) Hydrogen (B) Acetylene (C) LPG (D) Methane

MCQ 17 If L (mm) is the length of the inner cone of the flame, the tip-to-metal distance should be

(A) L mm (B) L + 2mm (C) L + 4mm (D) L + 6mm

MCQ 18 The correct flame for preheating before cutting is

(A) oxidizing flame (B) carburising flame (C) slightly carburizing flame (D) neutral flame

MCQ 19 While gas cutting the nozzle should

(A) almost touch the work (B) be 10 mm away from work (C) be 2 mm away from work (D) be 5 mm away from work

MCQ 20 If the blowpipe is moved to and fro frequently while cutting the kerf will

(A) not be affected (B) be less (C) of correct size (D) be more

MCQ 21 In gas cutting, if too little cutting oxygen is supplied

(A) the metal will be cooled down (B) the metal will fail to cut completely (C) the kerf will be narrow (D) the kert will be wide

MCQ 22 The top edge is melted round and the cut face is not smooth in gas cutting. This is due to

(A) the tip being held too high (B) too much cutting oxygen pressure (C) insufficient acetylene pressure (D) extremely slow cutting speed

MCQ 23 Cast iron contains two elements, which make it difficult to cut it by gas cutting.What are these elements

(A) Silicon and sulphur (B) Silicon and graphite (C) Graphite and phosphorous (D) Sulphur and phosphorous

MCQ 24 In a gas cut plate, the cut shows groove sand has deep drag lines. This is due to

(A) smaller size cutting nozzle (B) less oxygen pressure (C) too much travel speed (D) tip too close to the cut surface

MCQ 25 In a gas cut plate, the cut is high quality although there is some surface roughness caused by vertical drag lines.This is due to

(A) less preheating flame (B) impure cutting oxygen (C) too slow cutting speed (D) smaller size cutting nozzle