Start learning →

BHEL Engineer Trainee Abdmatrix — practice questions

Explore 3 free Abdmatrix questions in BHEL Engineer Trainee Mechanical Engineering. Open each question or exercise to read its content, reference answers and available explanation.

Practise Abdmatrix with Quill →

Abdmatrix questions and exercises with answers

Showing questions 1–3 of 3.

In CLT, the D matrix relates:Read the answer and worked solution →A CROSS-PLY laminate consists only of:Read the answer and worked solution →For a SYMMETRIC laminate, the 6×6 ABD system decouples into:Read the answer and worked solution →

Worked practice questions

In CLT, the D matrix relates:

  1. Strains to displacements
  2. Bending and twisting moment resultants {M_x, M_y, M_xy} to mid-plane curvatures {κ°_x, κ°_y, κ°_xy}
  3. In-plane forces to curvatures
  4. Shear stress to strain
Show answer and solution

Correct answer: B. Bending and twisting moment resultants {M_x, M_y, M_xy} to mid-plane curvatures {κ°_x, κ°_y, κ°_xy}

D is the bending stiffness matrix. Moment resultants per unit width (lb·in/in or N·m/m) couple to plate curvatures κ. D plays the role of EI for a 1D beam, generalized to a 2D plate.

Open this question →

A CROSS-PLY laminate consists only of:

  1. Plies at +45° and −45°
  2. Plies at 0° and 90° only (no off-axis angles)
  3. Plies at random angles
  4. Plies all at 0°
Show answer and solution

Correct answer: B. Plies at 0° and 90° only (no off-axis angles)

**Cross-ply:** only 0° and 90° plies. Naturally A_16 = A_26 = 0 (no off-axis terms) and, if symmetric, also D_16 = D_26 = 0. Used when bidirectional in-plane stiffness is wanted with simple design.

Open this question →

For a SYMMETRIC laminate, the 6×6 ABD system decouples into:

  1. Two 3×3 systems: in-plane {N} = A·{ε°} and bending {M} = D·{κ}
  2. Three 2×2 systems
  3. A single 6×6 system as before
  4. It does not decouple
Show answer and solution

Correct answer: A. Two 3×3 systems: in-plane {N} = A·{ε°} and bending {M} = D·{κ}

With B = 0, the upper-right and lower-left coupling blocks vanish. The full 6×6 collapses into independent 3×3 systems: forces ↔ in-plane strains via A, and moments ↔ curvatures via D. Massive analytical simplification.

Open this question →

How to practise

  1. Choose a Abdmatrix question and try to work out your answer.
  2. Open the question to check the correct answer and read its worked solution.
  3. Continue in the app for bite-sized lessons, explanations and review with Quill. You can start without creating an account.

More Mechanical Engineering topics

StressElasticityHookeslawStrainCompositesBiharmonicClassicallaminationtheoryKirchhoff