Activities vs. events – identify the incorrect statement Which of the following statements about project activities and events is wrong?
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AAn activity consumes time and resources, whereas an event does not.
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BThe performance of a specific task is called an activity.
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CAn event is an instantaneous point in time at which an activity begins or ends.
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DThe turning of a job on a lathe is an event, whereas “job turned” is an activity.
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ENone of the above
Answer
Correct Answer: The turning of a job on a lathe is an event, whereas “job turned” is an activity.
Explanation
Introduction / Context:Project networks distinguish between activities (work that takes time/resources) and events (milestones or instantaneous points). Confusing the two leads to faulty schedules and misleading progress tracking.
Given Data / Assumptions:
- Activity: time- and resource-consuming task (e.g., “turn job on lathe”).
- Event: a zero-duration milestone (e.g., “job turned”).
- We follow standard CPM/PERT terminology.
Concept / Approach:An activity is the process; an event is the state change marking its start or completion. Activities are represented by arrows or bars; events by nodes or milestones with zero duration.
Step-by-Step Solution:Identify which statement reverses definitions.“Turning of a job on a lathe” clearly consumes time/resources, so it is an activity.“Job turned” signifies completion, which is an event (instantaneous).Therefore, the given statement in option (d) is wrong.
Verification / Alternative check:Gantt or arrow diagrams label activities with durations; milestones have zero duration and mark “start” or “finish” events like “job turned.”
Why Other Options Are Wrong:Options (a), (b), and (c) correctly reflect standard definitions; option (e) cannot be true because one statement is indeed wrong.
Common Pitfalls:Treating milestones as buffer tasks; assigning resources to events.
Final Answer:The turning of a job on a lathe is an event, whereas “job turned” is an activity.