ISRO Scientist or Engineer Mechanical Dec 2017

Two dimensionally equal blocks made of material M1 and M2 are placed on flat horizontal surface as shown in figure below. Young’s modulus of the materials are El & E2 resp. A
uniform pressure ‘p’ is applied over the blocks through a thick plate (AB) symmetrically placed over the blocks. For E1 > E2, consider the statements below.

(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
Which of the above sentencesare correct?

In tolerancing of a part, unless otherwise specified, individual features of size must

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A 3 m long steel shaft has to transmit 7.5 kW at 3600 rpm. Required shaft diameter is given by (Take allowable shear stress = 100 N/mm$$^2$$, $$\pi^2 = 10$$)?

For thin cylindrical shell structures loaded in compression, the design is based on

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where ‘m’is the friction shear factor and ‘$$\overline{\sigma}$$’ is the flow stress

Governing differential equation for small deflections of elastic beamsis given by

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Isochoric changesin ideal gas are characterized by