1) Which stress is induced in a member, when expansion or contraction due to temperature variation is prevented?
a. Compressive stress
b. Tensile stress
c. Thermal stress
d. None of the above
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Answer
Explanation
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ANSWER: Thermal stress
Explanation:
No explanation is available for this question!
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2) The thermal stress induced in a steel rod is compressive, if temperature _____
a. decreases
b. increases
c. remains constant
d. none of the above
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Answer
Explanation
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ANSWER: increases
Explanation:
No explanation is available for this question!
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3) The deformation of a material caused due temperature variation develops ______
a. stress
b. strain
c. both a. and b.
d. none of the above
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Answer
Explanation
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ANSWER: none of the above
Explanation:
No explanation is available for this question!
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4) In the diagram shown below, material A and B expand freely as shown in condition (2). If expansion is prevented for equilibrium condition(3) to reach, then
a. tensile force exerted by material B on A is equal to tensile force exerted by A on B.
b. tensile force exerted by material B on A is equal to compressive force exerted by A on B.
c. compressive force exerted by material B on A is equal to tensile force exerted by A on B.
d. no force acts on the composite member in equilibrium conditions
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Answer
Explanation
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ANSWER: tensile force exerted by material B on A is equal to compressive force exerted by A on B.
Explanation:
No explanation is available for this question!
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5) Force of 100 kN is applied on 900 mm long rod of 20 mm diameter and is simultaneously heated at 70o C. What is the total elongation of the rod? (Assume coefficient of thermal expansion = 10 x 10–6 oC, Young's modulus = 150 Gpa)
a. 2.54 mm
b. 2.00 mm
c. 1.27 mm
d. 0.63 mm
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Answer
Explanation
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ANSWER: 2.54 mm
Explanation:
No explanation is available for this question!
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6) In a circuit box, a copper rod at room temperature of 25o C has a gap of 0.3 mm between the end of the rod Q and the rigid wall. If temperature of the rod increases to 70o C ,then what is the compressive stress acting on the rod PQ? (Assume Young's modulus = 100 Gpa & α = 15 x 10–6 /oC)
a. 6 Mpa
b. 7.5 Mpa
c. 8.2 Mpa
d. None of the above
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Answer
Explanation
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ANSWER: 7.5 Mpa
Explanation:
No explanation is available for this question!
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7) The value of elasticity increases, when temperature _____
a. increases
b. decreases
c. remains constant
d. none of the above
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Answer
Explanation
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ANSWER: decreases
Explanation:
No explanation is available for this question!
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8) If a composite bar of copper and steel is heated at 120o C, the stress induced in copper bar is _______
a. compressive stress
b. shear stress
c. tensile stress
d. thermal stress
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Answer
Explanation
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ANSWER: compressive stress
Explanation:
No explanation is available for this question!
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9) Thermal stress is not a function of _____
a. change in temperature
b. coefficient of linear expansion
c. modulus of elasticity
d. none of the above
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Answer
Explanation
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ANSWER: none of the above
Explanation:
No explanation is available for this question!
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10) What is the value of thermal stress, if a rod of 3 m is heated at 50 oC and is fixed at both the ends?
(Take α = 10 x 10-6 /oC & E= 200 x 103 Mpa)
a. 25 Mpa
b. 50 Mpa
c. 100 Mpa
d. 150 Mpa
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Answer
Explanation
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ANSWER: 100 Mpa
Explanation:
No explanation is available for this question!
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