1. A metal bar of length 200 m is inserted between 2 rigid supports and its temperature is increased by 30°C. If the coefficient of thermal expansion is 15 × 10^{-6} per °C and the Young’s modulus is 2 × 10^{5} MPa, then the stress in the

bar is

- 90,000 MPa
- 60 MPa
- 6000 MPa
- 90 MPa

2. If all the dimensions of a prismatic bar increase in the proportion n : 1, the proportion with which the maximum stress produced in the bar by its own weight will change by

- 1 : n
^{2} - 1 : n
- $\sqrt{n}$ : 1
- n : 1

3. A load of 100 kN suddenly acts on a bar of 100 cm^{2} area of cross-section and of length 300 mm. Maximum stress developed in the bar is

- 10 MPa
- 20 MPa
- 30 MPa
- 40 MPa

4. A rod 20 mm x 20 mm cross-section is carrying an axial tensile load 40 kN.what is the value of tensile stress developed in this rod?

- 100MPa
- 10 MPa
- 1 MPa
- 1000 MPa

5. A tube of aluminium of 40 mm external diameter and 20 mm internal diameter is snugly fitted on a solid steel rod of 20 mm diameter. The composite bar is subjected to an axial compressive force P. If the stress on steel bar is 70 N/mm^{2}, the stress in the aluminium tube and corresponding value of P will be: (E for steel: 2 × 10^{5} N/mm^{2} and E for aluminium: 7 × 10^{4} N/mm^{2})

- 24.5 N/mm
^{2}, 45.08 kN - 36.5 N/mm
^{2}, 60.10 kN - 54.5 N/mm
^{2}, 73.10 kN - 73.80 N/mm
^{2}, 92.60 kN

6. A Steel bar having cross-sectional area of 100π mm^{2} is subjected to a tensile force of 40 kN. Determine the tensile stress.

- 127.23 MPa
- 150 MPa
- 175.25 MPa
- 200.05 MPa

7. A square steel rod 20 mm × 20 mm in section is to carry an axial load of 100 kN. Calculate the stress.

- 1,50,000 kN/m
^{2} - 2,50,000 kN/m
^{2} - 4,50,000 kN/m
^{2} - 3,50,000 kN/m
^{2}

8. The stress due to suddenly applied load is _________ times that of gradually applied load.

- 5
- 4
- 3
- 2

9. A steel rod of length ‘L’ and diameter ‘d’ fixed at both ends, is uniformly heated to a temperature rise of ΔT. The modulus of elasticity of material is ‘E’ and Thermal expansion coefficient is ‘α’. Thermal stress in rod is

- EαΔTL
- αΔT
- EαΔT
- zero

10. Type of stress that causes dilation is known as

- Thermal stress
- Shear stress
- Deviatoric stress
- Hydrostatic stress

11. A steel bar of 5 mm is heated from 15° to 40°C and it is free to expand. The bar will induce

- No stress
- Shear stress
- Tensile stress
- Compressive stress

12. The stress in a steel bar is given as 25,0000 kN/m^{2} and length of the bar is 50 m. Calculate the shortening of the bar if E = 2.14 × 10^{8} N/mm^{2}

- 0.160 mm
- 0.0584 mm
- 0.250 mm
- 0.305 mm

13. A steel bar of 500 mm length is under tensile stress of 100 N/mm^{2}. If the modulus of elasticity is 2 × 10^{11} N/m^{2}, then the total elongation of the bar will be

- 2.50 mm
- 0.25 mm
- 0.50 mm
- 5.00 mm

14. A concrete beam is post-tensioned by a cable carrying an initial stress of 1000 N/mm^{2}, the slip of jacking end was observed to be 5 mm, modulus of steel is 210 kN/mm^{2} and span of beam is 30 m; what is % of loss of stress due to anchorage?

- 2.5%
- 3.5%
- 4.0%
- 1.5%

15. The rate of increase of stress is large in case of

- Unbonded beams
- Bonded beams
- Anchorage beams
- Tensioned beams

16. Subjected to axial load, the ductile material fails due to

- axial stress
- ductility
- axial strain
- shear stress

17. The unit of stress in S.I. unit is

- Kg/cm
^{2} - Kg/m
^{2} - N/m
^{2} - N/cm
^{2}

18. A bar of cross-sectional area 2 cm^{2} and length 100 cm fixed to rigid supports at both ends at a temperature of 25°C. The bar is subjected to an increase in temperature of 30°C. If the coefficient of linear thermal expansion of the

material is 10 × 10^{-6} °C and Young’s modulus is 2 × 10^{5} N/mm^{2}, the stress in the bar is

- 10 N/mm
^{2}comp - 20 N/mm
^{2}comp - 50 N/mm
^{2}tension - 50 N/mm
^{2}comp

19. The stress is ‘S’ when a body is subjected to a gradual load W on it. If the load is applied suddenly, the stress shall be

- S
- 2S
- 4S
- 1.5S

20. If a metal bar fixed at both ends is cooled by reducing the temperature by 30°C, the nature of the stress developed in the bar will be

- Shear
- Compressive
- Tensile
- None of the above