Practice Pakistan's most useful MCQs for competitive exams

Lug support is meant for supporting _______________ vessels?

• (A)  Large horizontal cylindrical
• (B)  Tall but empty
• (C)  Small
• (D)  Thick walled tall

Answer

Submitted By :Ali Uppal

The approximate liquid depth in an agitation tank is equal to (where, d = tank diameter)_________________?

• (A)  0.5 d
• (B)  0.75 d
• (C)  d
• (D)  2 d

Answer

Submitted By :Ali Uppal

Poisson’s ratio of a material is the ratio of unit lateral strain to the unit axial elongation within its elastic limit. The value of Poisson’s ratio for structural and pressure vessel steel may be taken as ____________________?

• (A)  0.01
• (B)  0.3
• (C)  0.75
• (D)  0.95

Answer

Submitted By :Ali Uppal

Steam is preferred to be used as a heating medium in heat exchangers, because of its_________________?

• (A)  Low cost
• (B)  High latent heat
• (C)  Non-corrosive condensate
• (D)  High film co-efficient

Answer

Submitted By :Ali Uppal

Diameter of rivet hole (d, mm) and the plate thickness (t, mm) are related by Unwin’s formula as___________________?

• (A)  d = 1.1 t
• (B)  d = 1.6 √t
• (C)  d = 1.5 t
• (D)  d = 3 √t

Answer

Submitted By :Ali Uppal

Overall mass transfer co-efficient in case of absorption of __________ in water is based on the gas film co-efficient only, as the mass transfer process is gas film (phase) controlling ?

• (A)  CO2
• (B)  SO2
• (C)  NH3
• (D)  None of these

Answer

Submitted By :Ali Uppal

Commercial packed scrubbers are normally designed for a pressure drop range of ______________ mm water column per metre of packed height?

• (A)  4-8
• (B)  17-34
• (C)  52-68
• (D)  88-105

Answer

Submitted By :Ali Uppal

For turbine agitator, the impeller diameter is about_________________?

• (A)  0.3 to 0.5 d
• (B)  0.1 to 0.2 d
• (C)  0.65 to 0.85 d
• (D)  0.95 d

Answer

Submitted By :Ali Uppal

The optimum size ratio for two mixed reactors in series depends on the kinetics of the reaction and the conversion level. For reaction orders more than one, the_________________?

• (A)  Equal sized reactors are the best
• (B)  Smaller reactor should come first
• (C)  Larger reactor should come first
• (D)  None of these

Answer

Submitted By :Ali Uppal

Circumferential (hoop) stress in a thin cylindrical vessel under internal pressure is _____________ the longitudinal stress?

• (A)  Half
• (B)  Equal to
• (C)  Twice
• (D)  Eight times

Answer

Submitted By :Ali Uppal