This set of Strength of Materials Multiple Choice Questions & Answers (MCQs) focuses on “Normal & Shear Stress”.
1. In the given figure a stepped column carries loads. What will be the maximum normal stress in the column at B in the larger diameter column if the ratio of P/A here is unity?
Explanation: Normal stress at B = Total load acting at B / Area of cross-section at B
= (P + P) / 1.5 A = 2P/ 1.5A = 2/1.5.
2. The stress which acts in a direction perpendicular to the area is called
a) shear stress
b) Normal stress
c) Thermal stress
d) None of the mentioned
Explanations: Normal stress acts in direction perpendicular to the area. Normal stress is of two types tensile and compressive stress.
3. Which of these are types of normal stresses?
a) Tensile and compressive stresses
b) Tensile and thermal stresses
c) Shear and bending
d) Compressive and plane stresses
Explanation: The normal stress is divided into tensile stress and compressive stress.
4. In a body loaded under plane stress conditions, what is the number of independent stress components ?
Explanation: In a body loaded under plane stress conditions, the number of independent stress components is 3 I.e. two normal components and one shear component.
5. If a bar of large length when held vertically and subjected to a load at its lower end, its won-weight produces additional stress. The maximum stress will be
a) At the lower cross-section
b) At the built-in upper cross-section
c) At the central cross-section
d) At every point of the bar
Explanation: The stress is the load per unit area. After the addition of weight in the bar due to its loading on the lower end the force will increase in the upper cross-section resulting the maximum stress at the built-in upper cross-section.
6. Which type of stress does in a reinforcement bar is taken by the concrete ?
a) Tensile stress
b) Compressive stress
c) Shear stress
d) Bending stress
Explanation: Concrete has the property of taking good amount of compressive stress. So, In the reinforcement bar the compressive stress is taken by the concrete.
7. A material has Poisson’s ratio of 0.5. If uniform pressure of 300GPa is applied to that material , What will be the volumetric strain of it?
Explanation: As volumetric strain = (1-2μ)σ/E
Here the value of μ is 0.5 so 1 – 2 * 0.5 becomes zero.
Therefore whatever be the stress the value of volumetric strain will be zero.
8. A diagram which shows the variations of the axial load for all sections of the pan of a beam, is called
a) Bending moment diagram
b) Shear force diagram
c) Thrust diagram
d) Stress diagram
Explanation: The stress diagram shows the variation of the axial load for all sections of the pan. The bending moment diagram shows the variation of moment in a beam. The shear force diagram shows the variation in the shear force due to loading in the beam.
9. The stress induced in a body, when subjected to two equal and opposite forces which are acting tangentially across the resisting section resulting the shearing of the body across its section is called
a) Bending stress
b) Compressive stress
c) Shear strain
d) Shear stress
Explanation: Shear stress makes the body to shear off across section. It is tangential to the area over which it acts. The corresponding strain is the shear strain.
10. What is the formula for shear stress?
a) Shear resistance / shear area
b) Force / unit area
c) Bending strain / area
d) Shear stress / length
Explanation: When force is applied, the twisting divides the body. The resistance is known as shear resistance and shear resistance per unit area is known as shear stress.
11. Which of the following stresses are associated with the tightening of nut on a bolt?
P. Crushing and shear stress in threads
Q. Bending stress due to the bending of bolt
R. Torsional shear stress due to frictional resistance between the nut and the bolt
Select the correct answer using the codes given below
a) P and Q
b) P and R
c) Only P
d) Only R
Explanation: Bending stress comes when there is some kind of eccentric load. Torsional stress will come when the nut is rotating. Shear stress will come in tightening of nut on bolt.
12. The transverse shear stress acting in a beam of rectangular cross-section, subjected to a transverse shear load, is
a) variable with maximum at the bottom of the beam
b) Variable with maximum at the top of the beam
d) Variable with maximum on the neutral axis
Explanation: Maximum value of shear stress at neutral axis is τ = 3/2 τmean
So, transverse shear stress is variable with maximum in the neutral axis.
13. A block 100mm x 100mm base and 10mm height. What will the direct shear stress in the element when a tangential force of 10kN is applied to the upper edge to a displacement 1mm relative to lower face?
Explanation: Shear stress = 10kN / 100mmx100mm = 1 N/mm2 = 1MPa.
Sanfoundry Global Education & Learning Series – Strength of Materials.
To practice all areas of Strength of Materials, here is complete set of 1000+ Multiple Choice Questions and Answers.