National Examination 04-BS-3, Statics and Dynamics — 2019-Dec. Candidates were required to complete 2 questions from PART A (Statics) and 2 questions from PART B (Dynamics); every question is solved below so this paper serves as a complete study resource (Questions 1-3 = paper Part A, I-III; Questions 4-6 = paper Part B, IV-VI).
Reference texts: Hibbeler, Engineering Mechanics: Statics (14th ed.); Hibbeler, Engineering Mechanics: Dynamics (14th ed.).
Check — source reconstruction notes. (2) Question 1's isometric figure gives explicit 1 m / 1.5 m dimensions along the rod, but plotting them on a single straight line makes the six rigid-body equilibrium equations inconsistent (no solution exists). Reading the printed figure, the horizontal run bends twice: A→C is 2 m along the first horizontal direction (with the vertical 1.5 m branch C→D), C→E is 1 m along the perpendicular horizontal direction (this is where the smooth journal bearing sits), and E→F is a further 1.5 m continuing the first horizontal direction to the point that carries the 250 N cylinder. This reading is the only one of the plausible alternatives that returns a statically-determinate, non-degenerate system, and it lands on the clean values reported below — strong corroborating evidence for the reconstruction. (3) Question 4's dimensions place the pin O exactly 90 mm above the floor, equal to the sphere radius (90 mm R); the sphere therefore contacts the floor exactly when the rod is horizontal, which is used as the impact configuration. (4) Question 6 numbers the four-bar linkage O-A-B-C from the source's own 100 mm / 250 mm / 75 mm / 50 mm dimensions; O and C are the fixed pivots, OA and CB are the driven/driving cranks and AB is the coupler.
