Topic: Mechanics of Materials
Two dimensionally equal blocks of material M1 and M2 are placed on a flat surface with Young's moduli E1 > E2. A uniform pressure 'p' is applied. Which of the following statements are correct? (p) Stress in both blocks are same (q) Strain in both blocks are same (r) Plate AB tilts and point B moves downward (s) Plate AB tilts and point A moves downward.
- A. p, q and r
- B. q and r
- C. p and s
- D. p and r
Answer: D. p and r
Explanation: Since pressure 'p' is uniform and blocks are dimensionally equal, the stress (P/A) is the same in both (p is correct). Since E1 > E2, strain (stress/E) will be different. Strain in M2 will be greater than M1, so block M2 will compress more, causing point B to move downward (r is correct).