FE Knowledge Flashcards
7 cards from real Fundamentals of Engineering practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 FE Knowledge flashcards as text
Which failure theory is most appropriate for ductile materials under static loading?
Answer: Maximum shear stress (Tresca) theory
The Tresca (maximum shear stress) criterion is commonly used and conservative for ductile materials under static loads.
For a second-order linear ODE with characteristic roots r = −2 ± 3i, the general solution is:
Answer: e^(-2t)(C₁cos3t + C₂sin3t)
Complex roots α ± βi give the solution e^(αt)(C₁cosβt + C₂sinβt); here α = −2, β = 3.
In Mohr's Circle for plane stress, the radius of the circle represents:
Answer: The maximum in-plane shear stress
The radius of Mohr's Circle equals the maximum in-plane shear stress τ_max.
Darcy-Weisbach equation is used to calculate:
Answer: Head loss due to friction in a pipe
The Darcy-Weisbach equation h_f = f(L/D)(V²/2g) computes frictional head loss in a pipe.
A capacitor of 100 μF is charged to 50 V. How much energy is stored?
Answer: 0.125 J
Energy W = ½CV² = ½ × 100×10⁻⁶ × 50² = ½ × 100×10⁻⁶ × 2500 = 0.125 J.
Which of the following correctly describes a statically indeterminate structure?
Answer: One where the number of unknowns exceeds the number of equilibrium equations
A statically indeterminate structure has more unknown reactions or member forces than available equilibrium equations.
The standard deviation of the data set {4, 8, 6, 5, 7} is closest to:
Answer: 1.41
Mean = 6; squared deviations: 4,4,0,1,1 → variance = 10/5 = 2; σ = √2 ≈ 1.41.