INTRODUCTION TO STRENGTH OF MATERIALS —- SHEET 3—THERMAL STRESSES, THERMAL STRAINS, POISSON’S RATIO, ELASTIC CONSTANTS, FACTOR OF SAFETY Thermal stress (σth) is there only when contraction due to fall of temperature is restricted——It is a tensile stress.=EαΔt Thermal stress (σth) is there only when expansion due to rise of temperature is restricted——- It is […]
INTRODUCTION TO STRENGTH OF MATERIALS–SHEET ———–Types of strains, modulus, stresses in composite sections, stresses due to suddenly and impact loads TYPES OF STRAINS : six Tensile strain, compressive strain, shear strain, linear strain, lateral strain and volumetric strain. Symbol for tensile strain =Є (epsilon) = δL/L = + in nature Symbol for compressive strain […]
Introduction to Strength of Materials—-SHEET 1–Various types of loads, Simple stresses This subject tells which materials are strong in tension/compression/bending/torsion/buckling loads. Hence depending upon the application, one can select the material for that application. Application includes chair, table, rod, shaft or any item one can think of. The selection is possible after performing tests […]
MECHANICAL PROPERTIES MECHANICAL ENGINEERING–Mechanical Properties–SHEET 2–Brittleness, Creep, Fatigue, Hardness, Malleability, Plasticity Brittleness A brittle material shows no deformation under any type of load. If the load is creased it will fail suddenly. Normally these materials fail due to small impact (moving) force. It has only one strength i.e. Ultimate strength. Brittle materials are cast iron, […]
MECHANICAL PROPERTIES–SHEET 1 –Ductility, Elasticity, Resilience, Yield strength. Stiffness, Toughness Materials/machines/structures are subjected to forces of one kind or the other or combined forces. How the materials behave under these forces is explained in terms of mechanical properties. These mechanical properties are measured by various destructive tests. Various worth mentioning mechanical properties are Ductility, Elasticity, […]
SOM—-INTERVIEW SHORT QUESTION ANSWERS ON STRENGTH OF MATERIALS – — strains, sudden load and impact load, Numerical problems on moment of inertia, elongation and Section modulus Write the relationship between true strain and conventional strain as well as relationship between true stress and conventional stress. A. When a tensile load is applied to a ductile material, its length […]
SOM—-INTERVIEW SHORT QUESTION ANSWERS ON STRENGTH OF MATERIALS —factor of safety, flexural rigidity, ductility, hoop stress, Hook’s Law, stress strain diagrams What is factor of safety? A. FACTOR OF SAFETY Need of the factor of safety is to account for uncertainties in the actual situation and the assumed situation. Because of many uncertainties, factor of safety is called […]
Multiple Choice Questions (mcq) on Strength of Materials –Gradually, suddenly and impact loads A gradually applied load is one (a) Which is increased 2 times every time (b) Which is increased in equal installments (c) Which is increased in any proportions (d) None (Ans: b) A suddenly applied load is one (a) Which is applied in […]
Multiple Choice Questions (mcq) on Strength of Materials –Factor of safety Factor of safety under gradually applied load is between (a) 2 and 4 (b) 4 and 8 (c) 8 and 16 (d) None (Ans: a) Factor of safety under suddenly applied load is between (a) 2 and 4 (b) 4 and 8 (c) 8 and […]
Multiple Choice Questions (mcq) on Strength of Materials— Forces — 2 A thermal force is always (a) Tensile (b) Compressive (c) Shear (d) None (Ans: d) A centrifugal force is a (a) Tensile (b) Compressive (c) Shear (d) None (Ans: a) A snow load is one (a) Constant in magnitude and direction (b) Variable magnitude […]