Free Plant Design and Economics MCQs with Answers

• A. 5-10
• B. 120-500
• C. 1000-1500
• D. 1500-3000

Explanation: Galvanized steel commonly carries about 120 to 500 g of zinc per square metre, depending on the required coating grade.

• A. Carburising
• B. Oxidising
• C. Neutral
• D. All A, B. & C

Explanation: A neutral flame supplies approximately equal oxygen and fuel and avoids adding excess carbon or oxygen to the weld.

• A. 2 and 50
• B. 10 and 50
• C. 7 and 30
• D. 13 and 55

Explanation: A private limited company requires at least two members and, under the stated conventional company-law limit, can have up to 50 members.

• A. Fatigue
• B. Tensile
• C. Impact
• D. None of these

Explanation: A tensile test produces a stress-strain curve, from which yield strength and Young's modulus are obtained; elongation and reduction in…

• A. Lead
• B. Graphite
• C. Stainless steel
• D. Cast iron

Explanation: Graphite crucibles tolerate very high temperatures and resist chemical attack by many molten metals.

• A. Tempered
• B. Normalised
• C. Annealed
• D. Hardened

Explanation: Annealing softens a cold-worked part and restores ductility by relieving residual stresses and reducing the effects of strain hardening.

• A. Mechanical
• B. Machining
• C. Refractory
• D. Magnetic

Explanation: A large silicon addition improves the magnetic behaviour of steel, particularly its electrical resistivity and suitability for transformer…

• A. Only
• B. Plus variable cost
• C. Plus overhead cost
• D. Plus selling expenses

Explanation: At break-even, total revenue equals total cost, and total cost is the sum of fixed cost and variable cost.

• A. Pitting
• B. Corrosion
• C. Erosion
• D. None of these

Explanation: Erosion is the removal or damage of a metal surface by mechanical action, such as impinging particles or a high-velocity fluid.

• A. Limit of proportionality
• B. Yield strength
• C. Elastic limit
• D. Fracture strength

Explanation: Metal-forming stresses must be high enough to cause plastic deformation, but they remain below the material’s fracture strength.

• A. Face centred cubic (fcc)
• B. Hexagonal close packed (hcp)
• C. Body centred cubic (bcc)
• D. None of these

Explanation: Face-centred cubic metals have many closely packed slip systems, allowing plastic deformation in several directions and giving high…

• A. Resource idleness
• B. Precedence relationship
• C. Resource restriction
• D. Necessary time delay

Explanation: A dummy activity in PERT has zero duration and consumes no resources; it is inserted only to show the correct precedence relationship…

• A. Flanged iron
• B. Flexible
• C. Collar
• D. Expansion

Explanation: Large-diameter RCC pipes are commonly connected using collar joints, in which a collar sleeve joins the adjoining pipe ends.

• A. H
• B. H/2
• C. H/4
• D. H/6

Explanation: The commonly specified minimum spacing between liquid-fuel storage tanks is H/6, where H is the tank height.

• A. Asbestos cement
• B. Steel
• C. Cement concrete
• D. Stoneware

Explanation: Steel sewer pipes have high strength and can withstand the internal pressure and mechanical stresses associated with pressurised sewage…

• A. Mean
• B. Inside
• C. Outside
• D. None of these

Explanation: Boiler tube dimensions are conventionally specified by wall thickness and outside diameter.

• A. Impact
• B. Torsion
• C. Charpy
• D. Hardness

Explanation: A hardness test leaves a small permanent indentation or other local mark, so it is commonly classified as semi-destructive.

• A. Tungsten, chromium & cobalt
• B. Nickel, cobalt & chromium
• C. Manganese, chromium & cobalt
• D. Tungsten, molybdenum & nickel

Explanation: Stellite alloys are cobalt-based hard-facing alloys whose important alloying elements include chromium and tungsten.

• A. 5
• B. 10
• C. 20
• D. 35

Explanation: Brasses containing more than about 20% zinc are especially prone to season cracking when residual tensile stress is present.

• A. Vacancy
• B. Dislocation
• C. All of these
• D. Grain boundary

Explanation: Annealing allows vacancies to diffuse, dislocations to recover, and grains to grow, reducing the densities of these defects in the…