Mechanical Properties of Solids Questions and Answers Part-14

1.A uniform cube is subjected to volume compression. If each side is decreased by 1%, then bulk strain is
a) 0.01
b) 0.06
c) 0.02
d) 0.03

Answer: d

2. A ball falling in a lake of depth 200 m shows 0.1% decrease in its volume at the bottom. What is the bulk modulus of the material of the ball
a) \[19.6\times 10^{8}N\diagup m^{2}\]
b) \[19.6\times 10^{-10}N\diagup m^{2}\]
c) \[19.6\times 10^{10}N\diagup m^{2}\]
d) \[19.6\times 10^{-8}N\diagup m^{2}\]

Answer: a

3.The isothermal bulk modulus of a gas at atmospheric pressure is
a) 1 mm of Hg
b) 13.6mm of Hg
c) \[1.013\times 10^{5}N\diagup m^{2}\]
d) \[2.026\times 10^{5}N\diagup m^{2}\]

Answer: c

4.Coefficient of isothermal elasticity \[E_{\theta}\] and coefficient of adiabatic elasticity \[E_{\phi}\] are related by\[\left(\gamma=C_{p}\diagup C_{v}\right)\]
a) \[E_{\theta}=\gamma E_{\phi}\]
b) \[E_{\phi}=\gamma E_{\theta}\]
c) \[E_{\theta}=\gamma \diagup E_{\phi}\]
d) \[E_{\theta}=\gamma^{2} E_{\phi}\]

Answer: b
Explanation: \[E_{\phi}=\gamma E_{\theta}\]

5. The bulk modulus of an ideal gas at constant temperature
a) Is equal to its volume V
b) Is equal to p/2
c) Is equal to its pressure p
d) Can not be determined

Answer: c
Explanation: Isothermal bulk modulus = Pressure of gas

6. The Bulk modulus for an incompressible liquid is
a) Zero
b) Unity
c) Infinity
d) Between 0 to 1

Answer: c
Explanation: Infinity

7. The pressure applied from all directions on a cube is P. How much its temperature should be raised to maintain the original volume ? The volume elasticity of the cube is \[\beta\] and the coefficient of volume expansion is \[\alpha\]
a) \[\frac{P}{\alpha\beta}\]
b) \[\frac{P\alpha}{\beta}\]
c) \[\frac{P\beta}{\alpha}\]
d) \[\frac{\alpha\beta}P{}\]

Answer: a

8. The pressure of a medium is changed from \[1.01\times 10^{5}Pa\]    to \[1.165\times 10^{5}Pa\]    and change in volume is 10% keeping temperature constant. The Bulk modulus of the medium is
a) \[204.8\times 10^{5}Pa\]
b) \[102.4\times 10^{5}Pa\]
c) \[51.2\times 10^{5}Pa\]
d) \[1.55\times 10^{5}Pa\]

Answer: d

9. Modulus of rigidity of diamond is
a) Too less
b) Greater than all matters
c) Less than all matters
d) Zero

Answer: b
Explanation: Greater than all matters

10. The ratio of lengths of two rods A and B of same material is 1 : 2 and the ratio of their radii is 2 : 1, then the ratio of modulus of rigidity of A and B will be
a) 4 : 1
b) 16 : 1
c) 8 : 1
d) 1 : 1

Answer: d
Explanation: Modulus of rigidity is the property of material.