Question 1

Achieving interchangeability of parts Which action most directly enables interchangeability in manufacturing and assembly?

Accepted Answer

Introduction / Context: Interchangeability means any part within a batch fits any mating part without selective assembly. It is fundamental to mass production and smooth service operations. Given Data / Assumptions: Designs specify limits and fits for mating features. Processes can hold tolerances consistently. Quality control verifies conformance. Concept / Approach: Standardisation defines common dimensions, GD&T, materials, and test methods so all suppliers and lines produce parts within agreed limits. With proper tolerancing (e.g., hole-basis system), parts assemble without hand-fitting. Step-by-Step Solution: Set functional requirements and allocate tolerances to features.Adopt standards (e.g., ISO fits) and common tooling gages.Control processes with SPC to keep variation within tolerance.Audit suppliers and lines for capability indices meeting targets. Verification / Alternative check: Low assembly rework, minimal selective fitting, and high first-pass yield indicate achieved interchangeability. Why Other Options Are Wrong: Process or product planning alone helps but without standardisation of specs and tolerances, interchangeability cannot be guaranteed. Bonus plans or inspection frequency do not inherently establish common standards. Common Pitfalls: Overly tight tolerances increasing cost, lack of datum schemes, and inconsistent measurement systems across suppliers. Final Answer: Standardisation (dimensions, tolerances, and specifications)

Question 2

Industrial engineering (wage plans): Which of the following wage incentive plans is designed to be applied across all workers in a plant, awarding bonuses based on measured efficiency against a standard?

Accepted Answer

Introduction / Context: Wage incentive plans in industrial engineering motivate higher productivity and align worker compensation with performance. Understanding which plan applies to all workers versus only those who save time on an assigned task helps select the right scheme for a factory or service operation. Given Data / Assumptions: A plant uses time standards developed via time study or predetermined motion time systems. “Applied to all workers” means every worker's bonus is calculated from a common efficiency metric, not just a few individuals who beat a specific time. Quality and safety levels are maintained; only acceptable output counts toward efficiency. Concept / Approach: Emerson's efficiency plan calculates an efficiency percentage (actual output or time versus standard). Below a threshold (often around two-thirds efficiency) workers receive guaranteed day wages; above that threshold, progressive bonuses are paid to all workers according to their efficiency level. By contrast, Halsey and Rowan are premium plans on a single job's saved time, and Gantt is a task-and-bonus differential plan. Step-by-Step Solution: Define efficiency% = (Standard time / Actual time) * 100 or (Actual output / Standard output) * 100.Apply a plant-wide bonus schedule that increases with efficiency beyond a set threshold.Ensure day-wage guarantee so low-efficiency workers still receive base pay.Outcome: every worker's pay can include a bonus, scaled by efficiency. Verification / Alternative check: Compare plan mechanics: Halsey/Rowan require time saved on a job; Gantt pays a high bonus only when a high standard is met. Only Emerson's explicitly scales bonuses for all workers via efficiency percent. Why Other Options Are Wrong: Halsey plan: Bonus applies to saved time on a job, not automatically to all workers. Gantt plan: Task-and-bonus or differential piece—bonus only if the task standard is met. Rowan plan: Bonus proportionate to time saved; again job-specific, not plant-wide efficiency for all. Common Pitfalls: Assuming “applied to all” means equal bonus; in Emerson's plan, bonus scales with each worker’s efficiency. Final Answer: Emerson's efficiency plan

Question 3

Facility planning: A process layout is also known by which of the following alternative names?

Accepted Answer

Introduction / Context: Facility layout strategy determines material flow, lead time, and flexibility. Process layout arranges similar machines together (functional layout) and is common in job shops. Many textbooks also use the terms analytical versus synthetic layouts; knowing these synonyms helps in exams and practice. Given Data / Assumptions: We are comparing standard layout types: process (functional), product (line), and fixed-position (static product). Terminology variations appear across curricula. Concept / Approach: Process layout = functional layout = analytical layout. Product layout (line) is sometimes called synthetic layout because it “synthesizes” operations into a sequence. Fixed-position layout is also called static product layout where the product stays in place and resources move to it. Step-by-Step Solution: Identify layout intent: group by process similarity = process layout.Recall synonyms: functional and analytical layout.Eliminate terms linked to other layouts (synthetic for product, static product for fixed-position). Verification / Alternative check: Cross-check with typical industrial engineering texts: process/functional/analytical are used interchangeably. Why Other Options Are Wrong: Synthetic layout: another name for product or line layout. Static product layout: refers to fixed-position projects (ships, aircraft assembly). None of these: incorrect since a correct synonym exists. Common Pitfalls: Confusing functional (process) with product (line) layouts; ignoring context-specific synonyms. Final Answer: Analytical layout

Question 4

Project networks (CPM/PERT): In network terminology, the actual performance or work content required to complete a task is called what?

Accepted Answer

Introduction / Context: CPM/PERT networks represent projects as connected elements. Distinguishing between activities, events, and durations is foundational to do forward/backward passes, compute floats, and identify the critical path. Given Data / Assumptions: Activity-on-Arrow or Activity-on-Node conventions may be used. Every task consumes time and possibly resources, regardless of representation. Concept / Approach: An activity is the performance of work that takes time and resources. An event (milestone) is a point in time indicating the start or finish of activities. Duration is the measured time an activity takes, not the work itself. Step-by-Step Solution: Identify the task (e.g., machine setup, pour concrete, test module).Represent it as an activity (arrow or node).Associate a duration with the activity based on estimates or data.Define start/finish events (AOA) or predecessor/successor links (AON). Verification / Alternative check: Check glossary in project management standards: “activity” explicitly denotes the work to be performed. Why Other Options Are Wrong: Event: a zero-duration point signifying completion or start, not the work itself. Duration: the length of time, not the task. None of these: incorrect because activity is the correct term. Common Pitfalls: Calling milestones “activities”; forgetting that dummy activities in AOA have zero duration and carry logic only. Final Answer: An activity

Question 5

Fundamentals of project management: Is PERT (Programme Evaluation and Review Technique) a recognised technique for project planning and control?

Accepted Answer

Introduction / Context: PERT is a probabilistic technique developed to plan and control projects with uncertain activity durations. It complements CPM, which traditionally uses deterministic times, but both are used for planning, scheduling, and control. Given Data / Assumptions: Projects consist of interdependent activities with precedence constraints. Uncertainty in task durations is material (R&D, new-product development). Concept / Approach: PERT models activity time with three estimates: optimistic, most likely, and pessimistic. Expected time te = (to + 4tm + tp) / 6. By building a network, one identifies the critical path, expected project duration, and variance for schedule risk analysis. Step-by-Step Solution: List activities with precedence relations.Elicit to, tm, tp and compute te and variance for each activity.Perform forward/backward pass to find ES, EF, LS, LF, floats.Use path variance to estimate completion probability for a deadline. Verification / Alternative check: Compare with CPM: while approaches differ in time estimates, both are used widely for planning and control, validating the statement. Why Other Options Are Wrong: “No” ignores the well-documented use of PERT for project planning and monitoring. Common Pitfalls: Assuming PERT eliminates uncertainty; it structures and quantifies it, aiding control decisions. Final Answer: Yes

Industrial Engineering and Production Management Questions