Practice Pakistan's most useful MCQs for competitive exams

Capacity of flight conveyor in tons/hr is given by (where, W & D = width and depth of flight respectively in metre V = speed of the conveyor, metre/second ρ = bulk density of material, kg/m3) ?

• (A)  3.6 W.D.V.ρ
• (B)  3.6 W.D.V
• (C)  3.6 W.V.ρ
• (D)  3.6

Answer

Submitted By :Ali Uppal

Addition of filter aid to the slurry before filtration is done to _______________ of the cake?

• (A)  Increase the porosity
• (B)  Increase the compressibility co-efficient
• (C)  Decrease the porosity
• (D)  Decrease the compressibility co-efficient

Answer

Submitted By :Ali Uppal

Sulphuric acid mist is arrested by using a ____________ scrubber?

• (A)  Packed wet
• (B)  Hollow wet
• (C)  Venturi
• (D)  Co-current

Answer

Submitted By :Ali Uppal

Which of the following must be stored in silos and not in open yard ?

• (A)  Coke breeze
• (B)  High V.M. bituminous coal
• (C)  Sand
• (D)  None of these

Answer

Submitted By :Ali Uppal

Froth floatation is the most suitable for treating ____________________?

• (A)  Iron ores
• (B)  Sulphide ores
• (C)  Quartzite
• (D)  None of these

Answer

Submitted By :Ali Uppal

Mixer used for rubber compounding is__________________?

• (A)  mixer-extruder
• (B)  Banbury internal mixer
• (C)  Muller mixer
• (D)  Pug mill

Answer

Submitted By :Ali Uppal

Half the angle of nip, (α), for a roll crusher is given by (where, dr, dp and df are diameters of crushing rolls, feed particles and rolls gap respectively) ?

• (A)  cos α = (dr + dp)/(dr + df)
• (B)  cos α = (dr + df)/(dr + dp)
• (C)  tan α = (dr + dp)/(dr + df)
• (D)  sin α = (dr + dp)/(dr + df)

Answer

Submitted By :Ali Uppal

Which of the following can be most effectively used for clarification of lube oil and printing ink ?

• (A)  Sparkler filter
• (B)  Pre-coat filter
• (C)  Disc-bowl centrifuge
• (D)  Sharpies super-centrifuge

Answer

Submitted By :Ali Uppal

For achieving maximum capacity of the ball mill, the ball charge should be equal to about ______________ percent of the ball mill volume?

• (A)  10
• (B)  25
• (C)  50
• (D)  75

Answer

Submitted By :Ali Uppal

_______________ mill is normally used for grinding of talc?

• (A)  Tube
• (B)  Compartment
• (C)  Ring-roll
• (D)  Pebble

Answer

Submitted By :Ali Uppal