A) 1.40 Ns/m done clear
B) 52.22 Ns/m done clear
C) 52.92 Ns/m done clear
D) 529.20 Ns/m done clear
View Solution play_arrowA) \[\frac{{{l}_{1}}+{{l}_{2}}+{{l}_{3}}}{3}\] done clear
B) \[{{l}_{1}}+{{l}_{2}}{{\left( \frac{{{d}_{1}}}{{{d}_{2}}} \right)}^{3}}+{{l}_{3}}{{\left( \frac{{{d}_{1}}}{{{d}_{3}}} \right)}^{3}}\] done clear
C) \[{{l}_{1}}+{{l}_{2}}{{\left( \frac{{{d}_{1}}}{{{d}_{2}}} \right)}^{4}}+{{l}_{3}}{{\left( \frac{{{d}_{1}}}{{{d}_{3}}} \right)}^{4}}\] done clear
D) \[{{l}_{1}}+{{l}_{2}}+{{l}_{3}}\] done clear
View Solution play_arrowA) \[46\text{ }Hz\] done clear
B) \[3\,\,\pi Hz\] done clear
C) \[3\text{ }Hz\] done clear
D) \[6\,\pi Hz\] done clear
View Solution play_arrow1. Logarithmic method |
2. Band-width method |
3. Rayleigh method |
4. Holzer method, |
Select the correct answer using the codes given below: |
A) 1 and 3 done clear
B) 1 and 2 done clear
C) 3 and 4 done clear
D) 1, 3 and 4 done clear
View Solution play_arrowA) 0.5 done clear
B) 1.0 done clear
C) 1.5 done clear
D) 2.0 done clear
View Solution play_arrowA) \[\frac{1}{2}N\] done clear
B) \[\frac{1}{\sqrt{2}}N\] done clear
C) N done clear
D) 2N done clear
View Solution play_arrowA) Primary critical speed effect done clear
B) Secondary critical speed effect done clear
C) Unbalanced parts of the fan done clear
D) Aerodynamic unbalance done clear
View Solution play_arrowA) \[\beta <1\] done clear
B) \[\beta =1\] done clear
C) \[\beta >1\] done clear
D) \[\beta <<1\] done clear
View Solution play_arrowA) 0.25 done clear
B) 0.50 done clear
C) 1.00 done clear
D) sqrt 2 done clear
View Solution play_arrowA) Return to equilibrium position without oscillation done clear
B) Oscillate with increasing time period done clear
C) Oscillate with decreasing amplitude done clear
D) Oscillate with constant amplitude done clear
View Solution play_arrowquestion_answer11) Under logarithmic decrement, the amplitude of successive vibrations are:
A) constant done clear
B) In arithmetic progression done clear
C) In geometric progression done clear
D) In logarithmic progression done clear
View Solution play_arrowquestion_answer12) The danger of breakage and vibration is maximum:
A) Below critical speed done clear
B) near critical speed done clear
C) Above critical speed done clear
D) none of the above done clear
View Solution play_arrowA) Free vibration with damping done clear
B) Free vibration without damping done clear
C) Forced vibration with damping done clear
D) Forced vibration without damping done clear
View Solution play_arrowA) N/2 done clear
B) 2N done clear
C) 4N done clear
D) 8N done clear
View Solution play_arrowquestion_answer15) Rotating shafts tend to vibrate violently at whirling speeds because:
A) The shafts are rotating at very high speeds done clear
B) Bearing centre line coincides with the shaft axis done clear
C) The system is unbalanced done clear
D) Resonance is caused due to the heavy weight of the rotor. done clear
View Solution play_arrowA) Transverse vibrations done clear
B) Torsional vibrations done clear
C) Longitudinal vibrations done clear
D) Longitudinal vibrations provided the shaft is vertical. done clear
View Solution play_arrowA) Zero done clear
B) Also one revolution in the same direction done clear
C) Also one revolution but in the opposite direction done clear
D) unpredictable done clear
View Solution play_arrowA) 10 done clear
B) 50 done clear
C) 100 done clear
D) 200 done clear
View Solution play_arrowA) \[0.170\times {{10}^{-\,4}}m\] done clear
B) \[1.000\times {{10}^{-\,4}}m\] done clear
C) \[1.274\times {{10}^{-\,4}}m\] done clear
D) \[2.540\times {{10}^{-\,4}}m\] done clear
View Solution play_arrowList-I (Force transmissibility) | List-II (Frequency ratio) | ||
A. | 1 | 1. | \[\frac{\omega }{{{\omega }_{n}}}>\sqrt{2}\] |
B. | Less than 1 | 2. | \[\frac{\omega }{{{\omega }_{n}}}=\sqrt{2}\] |
C. | Greater than 1 | 3. | \[\frac{\omega }{{{\omega }_{n}}}>>\sqrt{2}\] |
D. | Tending to zero | 4. | \[\frac{\omega }{{{\omega }_{n}}}<\sqrt{2}\] |
A) A\[\to \]1, B\[\to \]2, C\[\to \]3, D\[\to \]4 done clear
B) A\[\to \]2, B\[\to \]1, C\[\to \]4, D\[\to \]3 done clear
C) A\[\to \]2, B\[\to \]1, C\[\to \]3, D\[\to \]4 done clear
D) A\[\to \]1, B\[\to \]2, C\[\to \]4, D\[\to \]3 done clear
View Solution play_arrowA) \[\frac{9}{128}\] done clear
B) \[\frac{9}{16}\] done clear
C) \[\frac{9}{8\sqrt{2}}\] done clear
D) \[\frac{9}{8}\] done clear
View Solution play_arrowquestion_answer22) The critical speed of a rotating shaft depends
A) Mass done clear
B) Stiffness done clear
C) Mass and stiffness done clear
D) Mass, stiffness and eccentricity. done clear
View Solution play_arrowA) \[{{l}_{1}}+{{l}_{2}}+{{l}_{3}}\] done clear
B) \[\frac{{{l}_{1}}+{{l}_{2}}+{{l}_{3}}}{3}\] done clear
C) \[{{l}_{1}}+{{l}_{2}}{{\left( \frac{{{d}_{1}}}{{{d}_{2}}} \right)}^{3}}+{{l}_{3}}{{\left( \frac{{{d}_{1}}}{{{d}_{3}}} \right)}^{3}}\] done clear
D) \[{{l}_{1}}+{{l}_{2}}{{\left( \frac{{{d}_{1}}}{{{d}_{2}}} \right)}^{4}}+{{l}_{3}}{{\left( \frac{{{d}_{1}}}{{{d}_{3}}} \right)}^{4}}\] done clear
View Solution play_arrowA) \[\sqrt{\frac{k}{m+\frac{{{m}_{s}}}{3}}}\] done clear
B) \[\sqrt{\frac{k}{\frac{m}{3}+{{m}_{s}}}}\] done clear
C) \[\sqrt{\frac{3k}{m+{{m}_{s}}}}\] done clear
D) \[\sqrt{\frac{k}{m+{{m}_{s}}}}\] done clear
View Solution play_arrowList-I | List-II | ||
A. | Node and mode | 1. | Geared vibration |
B. | Equivalent inertia | 2. | Damped-free vibration |
C. | Log decrement | 3. | Forced vibration |
D. | Resonance | 4. | Multi-rotor vibration |
A) A\[\to \]1, B\[\to \]4, C\[\to \]3, D\[\to \]2 done clear
B) A\[\to \]4, B\[\to \]1, C\[\to \]2, D\[\to \]3 done clear
C) A\[\to \]1, B\[\to \]4, C\[\to \]2, D\[\to \]3 done clear
D) A\[\to \]4, B\[\to \]1, C\[\to \]3, D\[\to \]2 done clear
View Solution play_arrowA) \[{{\left( \frac{m{{l}^{3}}}{48EI} \right)}^{\frac{1}{2}}}\text{rad/s}\] done clear
B) \[{{\left( \frac{48m{{l}^{3}}}{EI} \right)}^{\frac{1}{2}}}\text{rad/s}\] done clear
C) \[{{\left( \frac{48EI}{m{{L}^{3}}} \right)}^{\frac{1}{2}}}\text{rad/s}\] done clear
D) \[{{\left( \frac{3EI}{m{{L}^{3}}} \right)}^{\frac{1}{2}}}\text{rad/s}\] done clear
View Solution play_arrowA) Infinity done clear
B) Inversely proportional to damping done clear
C) Directly proportional to damping done clear
D) Decreasing exponentially with time done clear
View Solution play_arrowA) Equal to natural frequency done clear
B) Slightly less than natural frequency done clear
C) Slightly greater than natural frequency done clear
D) Zero done clear
View Solution play_arrowquestion_answer29) The value of the natural frequency obtained by Rayleigh's method:
A) Is always greater than the actual fundamental frequency done clear
B) Is always less than the actual fundamental frequency done clear
C) Depends upon the initial deflection curve chosen and may be greater than or less than the actual fundamental frequency done clear
D) Is independent of the initial deflection curve chosen. done clear
View Solution play_arrowA) Two done clear
B) Equal to the number of rotor plus one done clear
C) Equal to the number of rotors done clear
D) Equal to the number of rotors minus one done clear
View Solution play_arrowA) Be double done clear
B) Increase by \[\sqrt{2}\] times done clear
C) Decrease by \[\sqrt{2}\] times done clear
D) Be half done clear
View Solution play_arrowquestion_answer32) The damping force in forced vibrations with reference to spring force:
A) Leads by \[90{}^\circ \] done clear
B) Lags by \[90{}^\circ \] done clear
C) Leads by \[180{}^\circ \] done clear
D) Lags by \[180{}^\circ \] done clear
View Solution play_arrowList-I | List-II | ||
A. | 6 d.o.f. system | 1. | Vibrating beam |
B. | 1 d.o.f. system | 2. | Vibration absorber |
C. | 2 d.o.f. system | 3. | A rigid body in space |
D. | Multi d.o.f. system | 4. | Pure rolling of a cylinder |
A) A\[\to \]1, B\[\to \]2, C\[\to \]4, D\[\to \]5 done clear
B) A\[\to \]1, B\[\to \]4, C\[\to \]2, D\[\to \]3 done clear
C) A\[\to \]3, B\[\to \]2, C\[\to \]4, D\[\to \]1 done clear
D) A\[\to \]3, B\[\to \]4, C\[\to \]2, D\[\to \]1 done clear
View Solution play_arrowA) \[\frac{1}{{{\left[ \frac{{{\omega }_{c}}}{\omega } \right]}^{2}}+1}\] done clear
B) \[\frac{1}{{{\left[ \frac{{{\omega }_{c}}}{\omega } \right]}^{2}}-1}\] done clear
C) \[{{\left[ \frac{{{\omega }_{c}}}{\omega } \right]}^{2}}+1\] done clear
D) \[\frac{\omega }{{{\left[ \frac{{{\omega }_{c}}}{\omega } \right]}^{2}}-1}\] done clear
View Solution play_arrowA) Mass of the vehicle, stiffness of the suspension spring, speed of the vehicle, wavelength of the roughness curve done clear
B) Speed of the vehicle only done clear
C) Speed of the vehicle and the stillness of the suspension spring done clear
D) Amplitude of the undulations done clear
View Solution play_arrowquestion_answer36) During torsional vibration of a shaft, the node is characterized by the:
A) Maximum angular velocity done clear
B) Maximum angular displacement done clear
C) Maximum angular acceleration done clear
D) Zero angular displacement done clear
View Solution play_arrowA) \[\frac{1}{2\pi }\sqrt{\frac{g}{l}}\] done clear
B) \[\frac{1}{2\pi }\sqrt{\frac{g}{3l}}\] done clear
C) \[\frac{1}{2\pi }\sqrt{\frac{2g}{3l}}\] done clear
D) \[\frac{1}{2\pi }\sqrt{\frac{3g}{2l}}\] done clear
View Solution play_arrowA) 80 cm done clear
B) 90 cm done clear
C) 100 cm done clear
D) 110 cm done clear
View Solution play_arrowA) 810 done clear
B) 900 done clear
C) 800 done clear
D) 820 done clear
View Solution play_arrowquestion_answer40) What is the number of nodes in a shalt carrying three rotors?
A) Zero done clear
B) 2 done clear
C) 3 done clear
D) 4 done clear
View Solution play_arrowA) Vibration of a stretched string done clear
B) Motion of a projectile in a gravitational field done clear
C) Heat flow in thin rod done clear
D) Oscillation of a simple pendulum done clear
View Solution play_arrowA) 60 done clear
B) 75 done clear
C) 80 done clear
D) 100 done clear
View Solution play_arrowA) 1kg done clear
B) 1.6 kg done clear
C) 2 kg done clear
D) 2.4 kg done clear
View Solution play_arrowA) Is less than \[\sqrt{2}\] done clear
B) is greater than \[\sqrt{2}\] done clear
C) Is less than \[\frac{1}{\sqrt{2}}\] done clear
D) is greater than \[\frac{1}{\sqrt{2}}\] done clear
View Solution play_arrowA) \[2\,\,{{\omega }_{cr}}\] done clear
B) \[\sqrt{2}\,\,{{\omega }_{cr}}\] done clear
C) \[{{\omega }_{cr}}\] done clear
D) \[\frac{1}{2}\,\,{{\omega }_{cr}}\] done clear
View Solution play_arrowquestion_answer46) The silencer of an internal combustion engine:
A) Reduces noise done clear
B) Decreases brake specific fuel consumption (BSFC) done clear
C) Increases BSFC done clear
D) Has no effect on its efficiency done clear
View Solution play_arrowA) 20 mm done clear
B) 10 mm done clear
C) 5 mm done clear
D) 2.5 mm done clear
View Solution play_arrowA) 60 Hz done clear
B) 90 Hz done clear
C) 135 Hz done clear
D) 180 Hz done clear
View Solution play_arrowA) \[\frac{1}{2}\] done clear
B) \[\frac{3}{4}\] done clear
C) \[\frac{4}{3}\] done clear
D) 2 done clear
View Solution play_arrowA) Enthalpy done clear
B) Internal energy done clear
C) Entropy done clear
D) Volume done clear
View Solution play_arrowA) 20 kJ done clear
B) 30 kJ done clear
C) 40 kJ done clear
D) 50 kJ done clear
View Solution play_arrowA) \[{{l}_{a}}=\frac{L{{l}_{b}}}{{{I}_{a}}+{{I}_{b}}}\] done clear
B) \[{{l}_{a}}=\frac{L{{l}_{a}}}{{{I}_{a}}+{{I}_{b}}}\] done clear
C) \[{{l}_{a}}=\frac{L{{l}_{b}}}{{{I}_{a}}+{{I}_{b}}-1}\] done clear
D) \[{{l}_{a}}=\frac{L{{l}_{a}}}{{{I}_{a}}+{{I}_{b}}-1}\] done clear
View Solution play_arrowA) More than \[\sqrt{2}\] done clear
B) less than \[\sqrt{2}\] done clear
C) Equal to one done clear
D) less than one done clear
View Solution play_arrowA) Equal to natural frequency done clear
B) Slightly less than natural frequency done clear
C) Slightly greater than natural frequency done clear
D) Zero. done clear
View Solution play_arrowquestion_answer55) The rotor of a turbine is generally rotated at:
A) The critical speed done clear
B) A speed much below the critical speed done clear
C) A speed much above the critical speed done clear
D) A speed having no relation to critical speed done clear
View Solution play_arrowquestion_answer56) A reed type tachometer uses the principle of:
A) Torsional vibration done clear
B) Longitudinal vibration done clear
C) Transverse vibration done clear
D) Damped free vibration done clear
View Solution play_arrowA) zero done clear
B) less than one done clear
C) Equal to one done clear
D) greater than one done clear
View Solution play_arrowA) \[\sqrt{\frac{k}{m-\frac{{{m}_{s}}}{3}}}\] done clear
B) \[\sqrt{\frac{k}{m+\frac{{{m}_{s}}}{3}}}\] done clear
C) \[\sqrt{\frac{k}{m+3{{m}_{s}}}}\] done clear
D) \[\sqrt{\frac{k}{m-3{{m}_{s}}}}\] done clear
View Solution play_arrowquestion_answer59) Consider the following methods:
1. Energy method |
2. Equilibrium method |
3. Rayleigh's method. |
A) 1 and 2 done clear
B) 1, 2 and 3 done clear
C) 1 and 3 done clear
D) 2 and 3 done clear
View Solution play_arrowquestion_answer60) Consider the following statements:
1. In forced vibrations the body vibrates under the influence of an applied force. |
2. In damped vibrations amplitude reduces over every cycle of vibration |
3. In torsional vibrations the disc moves parallel to the axis of shaft. |
4. in transverse vibrations the particles of the shaft moves approximately perpendicular to the axis of the shaft. |
A) 1, 2 and 3 done clear
B) 1, 3 and 4 done clear
C) 2, 3 and 4 done clear
D) 1, 2 and 4 done clear
View Solution play_arrowquestion_answer61) Whirling speed of shaft is the speed at which:
A) Shaft tends to vibrate in longitudinal direction done clear
B) Torsional vibrations occur done clear
C) Shaft tends to vibrate vigorously in transverse direction done clear
D) Combination of transverse and longitudinal vibration occurs. done clear
View Solution play_arrowA) 5367 rpm done clear
B) 6000 rpm done clear
C) 9360 rpm done clear
D) 12000 rpm done clear
View Solution play_arrowA) Critical damping ratio done clear
B) Damping factor done clear
C) Logarithmic decrement done clear
D) Magnification factor done clear
View Solution play_arrow1. The kinetic energy of the equivalent system is equal to that of the original system. |
2. The strain energy of the equivalent system is equal to that of the original system. |
3. The shaft diameters of the two systems are equal. |
A) 1, 2 and 3 done clear
B) 1 and 2 done clear
C) 2 and 3 done clear
D) 1 and 3 done clear
View Solution play_arrowA) \[\frac{\sqrt{3}}{2}\] done clear
B) \[\frac{1}{2}\] done clear
C) \[\frac{1}{\sqrt{2}}\] done clear
D) \[\frac{1}{4}\] done clear
View Solution play_arrowA) \[\frac{\omega }{{{\omega }_{n}}}\] is zero and \[\sqrt{3}\] for all values of damping done clear
B) \[\frac{\omega }{{{\omega }_{n}}}\] is zero and \[\sqrt{2}\] for all values of damping done clear
C) \[\frac{\omega }{{{\omega }_{n}}}\] is unity and 2 for all values of damping done clear
D) \[\frac{\omega }{{{\omega }_{n}}}\] is unity and \[\sqrt{3}\] for all values of damping. done clear
View Solution play_arrowA) \[{{l}_{1}}\] is changed to \[{{G}^{2}}{{I}_{1}}\] done clear
B) \[{{I}_{2}}\] is changed to \[{{G}^{2}}{{I}_{2}}\] done clear
C) \[{{I}_{1}}\] is changed to \[{{\text{I}}_{\text{1}}}\text{/}{{\text{G}}^{\text{2}}}\] done clear
D) \[{{I}_{2}}\] is changed to \[{{\text{I}}_{2}}\text{/}{{\text{G}}^{\text{2}}}\] done clear
View Solution play_arrowA) 1/5 m done clear
B) 4/5 m done clear
C) 1/25 m done clear
D) 16/25 m done clear
View Solution play_arrowquestion_answer69) Which one of the following is realized by hydraulic dashpot shock absorbers?
A) Viscous damping done clear
B) Structural damping done clear
C) Coulomb damping done clear
D) spring damping done clear
View Solution play_arrowA) Force applied to the machine to the force transmitted to the foundation done clear
B) Force transmitted to the foundation to the force applied to the machine done clear
C) Force applied to the machine to the vector sum of spring forces done clear
D) Damping forces to the spring forces. done clear
View Solution play_arrowA) It has no node done clear
B) It has one node done clear
C) It has two nodes done clear
D) It has three nodes done clear
View Solution play_arrowA) 5367 rpm done clear
B) 6000 rpm done clear
C) 9360 rpm done clear
D) 12,000 rpm done clear
View Solution play_arrowA) 2 mm done clear
B) 225 mm done clear
C) 2.50 mm done clear
D) 3.00 mm done clear
View Solution play_arrowA) 1 done clear
B) 10 done clear
C) 100 done clear
D) infinite done clear
View Solution play_arrowquestion_answer75) Coulomb damping results from which one of the following?
A) Dry friction between moving parts done clear
B) Drag between a moving body and the fluid environment done clear
C) Internal friction within a material done clear
D) Radiation of energy into the environmentl. done clear
View Solution play_arrowquestion_answer76) Consider the following statements:
1. When frequency ratio is < 2, the force transmitted to the foundation is more than the exciting force. |
2. When frequency ratio is > 2, the force transmitted to the foundation increases and the damping is decreased. |
3. The analysis of base excited vibrations is similar to that of forced vibrations. |
A) 1 and 2 done clear
B) 2 and 5 done clear
C) 1 and 3 done clear
D) 1, 2 and 3 done clear
View Solution play_arrowquestion_answer77) Consider the following statements:
1. Critical or whirling speed of the shaft is the speed at which it tends to vibrate violently in the transverse direction. |
2. To find the natural frequency of a shaft carrying several loads, the energy method gives approximate results. |
3. Dunkerley's method gives accurate results of the natural frequency of a shaft carrying several loads. |
A) 1 only done clear
B) 2 and 3 done clear
C) 1 and 3 done clear
D) 1, 2 and 3 done clear
View Solution play_arrowA) \[Equal\,\,to\,\,1\] done clear
B) <1 done clear
C) \[<\sqrt{2}\] done clear
D) \[>\sqrt{2}\] done clear
View Solution play_arrowA) Inertia force leads damping force by \[90{}^\circ \] while damping force leads spring force by\[90{}^\circ \]. done clear
B) Spring force leads damping force by \[90{}^\circ \] while damping force leads inertia force by\[180{}^\circ \]. done clear
C) Spring force and damping force are in phase, and inertia force leads them by \[90{}^\circ \] done clear
D) Spring force and inertia force are in phase, and damping force leads them by \[90{}^\circ \] done clear
View Solution play_arrowA) \[\frac{{{\omega }_{2}}-{{\omega }_{1}}}{{{\omega }_{n}}}\] done clear
B) \[\frac{{{\omega }_{2}}+{{\omega }_{1}}}{{{\omega }_{n}}}=\zeta \] done clear
C) \[\frac{{{\omega }_{2}}-{{\omega }_{1}}}{{{\omega }_{n}}}={{\zeta }^{2}}\] done clear
D) \[\frac{{{\omega }_{2}}-{{\omega }_{1}}}{{{\omega }_{n}}}=\zeta \] done clear
View Solution play_arrowList-I | List-II | ||
A. | Centre of pressure | 1. | Point of application of the weight of displaced liquid |
B. | Centre of gravity | 2. | Point about which the body starts oscillating when tilted by a small angle |
C. | Centre of buoyancy | 3. | Point of application of hydrostatic pressure |
D. | Metacentre | 4. | Point of application of the weight of the body |
A) A\[\to \]4, B\[\to \]3, C\[\to \]1, D\[\to \]2 done clear
B) A\[\to \]4, B\[\to \]3, C\[\to \]2, D\[\to \]1 done clear
C) A\[\to \]3, B\[\to \]4, C\[\to \]1, D\[\to \]2 done clear
D) A\[\to \]3, B\[\to \]4, C\[\to \]2, D\[\to \]1 done clear
View Solution play_arrowA) The metal piece will sink to the bottom done clear
B) The metal piece will simply float over the mercury with no immersion done clear
C) The metal piece will be immersed in mercury by half done clear
D) The whole of the metal piece will be immersed with its top surface just at mercury level done clear
View Solution play_arrowA) An increased reading done clear
B) A decreased reading done clear
C) No change in reading done clear
D) Increased or decreased reading depending on the depth of immersion done clear
View Solution play_arrowA) 42.41 s done clear
B) 75.4 s done clear
C) 20.85 s done clear
D) 85 s done clear
View Solution play_arrowA) \[0.146\,\,\text{N/}{{\text{m}}^{\text{2}}}\] done clear
B) \[0.73\,\,\text{N/}{{\text{m}}^{\text{2}}}\] done clear
C) \[146\,\,\text{N/}{{\text{m}}^{\text{2}}}\] done clear
D) \[292\,\,\text{N/}{{\text{m}}^{\text{2}}}\] done clear
View Solution play_arrowquestion_answer86) Newton's law of viscosity depends upon the:
A) Stress and strain in a fluid done clear
B) Shear stress, pressure and velocity done clear
C) Shear stress and rate of strain done clear
D) Viscosity and shear stress done clear
View Solution play_arrowA) Reducing the shaft length done clear
B) Reducing the rotor mass done clear
C) Increasing the rotor mass done clear
D) Increasing the shaft diameter done clear
View Solution play_arrowList I (Surfaces with orientations) | List-II (Equivalent Emissivity) | ||
A. | Infinite parallel planes | 1. | \[{{\in }_{1}}\] |
B. | Body 1 completely enclosed by body 2 but body 1 is very small | 2. | \[\frac{1}{\frac{1}{{{\in }_{1}}}+\frac{1}{{{\in }_{2}}}-1}\] |
C. | Radiation exchange between two small gray bodies | 3. | \[\frac{1}{\frac{1}{{{\in }_{1}}}+\left( \frac{{{A}_{1}}}{{{A}_{2}}} \right)\left( \frac{1}{{{\in }_{2}}}-1 \right)}\] |
D. | Two concentric cylinders with large lengths | 4. | \[{{\in }_{1}}.{{\in }_{2}}\] |
A) A\[\to \]3, B\[\to \]1, C\[\to \]4, D\[\to \]2 done clear
B) A\[\to \]2, B\[\to \]4, C\[\to \]1, D\[\to \]3 done clear
C) A\[\to \]2, B\[\to \]1, C\[\to \]4, D\[\to \]3 done clear
D) A\[\to \]3, B\[\to \]4, C\[\to \]1, D\[\to \]2 done clear
View Solution play_arrowA) Greater than that of sphere B done clear
B) Less than that of sphere B done clear
C) Equal to that of sphere B done clear
D) Equal to double that of sphere B done clear
View Solution play_arrowA) 0.2 done clear
B) 0.4 done clear
C) 0.8 done clear
D) 1.0 done clear
View Solution play_arrowA) 1 done clear
B) 2 done clear
C) 3 done clear
D) 4 done clear
View Solution play_arrowA) 3650 K done clear
B) 4500 K done clear
C) 5800 K done clear
D) 6150 K done clear
View Solution play_arrowA) \[{{k}_{1}}+{{k}_{2}}\] done clear
B) \[{{k}_{1}}{{k}_{2}}\] done clear
C) \[\frac{{{k}_{1}}+{{k}_{2}}}{{{k}_{1}}{{k}_{2}}}\] done clear
D) \[\frac{2{{k}_{1}}{{k}_{2}}}{{{k}_{1}}+{{k}_{2}}}\] done clear
View Solution play_arrowA) Increase done clear
B) Decrease done clear
C) Remain the same done clear
D) Vary depending upon the electric conductivity of the wire. done clear
View Solution play_arrowA) Double of the original value done clear
B) Half of the original value done clear
C) Same as before done clear
D) Four times of the original value. done clear
View Solution play_arrowA) Ammonia reciprocating compressor done clear
B) Centrifugal Chiller done clear
C) Absorption refrigeration system done clear
D) Hermetic compressor done clear
View Solution play_arrowA) 1/2 done clear
B) 3/2 done clear
C) 9/2 done clear
D) 25/2 done clear
View Solution play_arrowquestion_answer98) Air refrigeration cycle is used in:
A) Commercial refrigerators done clear
B) Domestic refrigerators done clear
C) Gas liquefaction done clear
D) Air-conditioning done clear
View Solution play_arrowquestion_answer99) The flash chamber in a single stage simple vapour compression cycle:
A) Increase the refrigerating effect done clear
B) Decreases the refrigerating effect done clear
C) Increases the work of compression done clear
D) Has no effect on refrigerating effect done clear
View Solution play_arrowquestion_answer100) Consider the following statements:
In a vapour compression system, a thermometer placed in the liquid line can indicate whether the: |
1. Refrigerant flow is too low |
2. Water circulation is adequate. |
3. Condenser is fouled. |
4. Pump is functioning properly. |
A) 1, 2 and 3 are correct done clear
B) 1, 2 and 4 are correct done clear
C) 1, 3 and 4 are correct done clear
D) 2, 3 and 4 are correct done clear
View Solution play_arrowList-I | List-II | ||
A. | Bell Column refrigeration | 1. | Compressor |
B. | Vapour compression refrigeration | 2. | Generator |
C. | Absorption refrigeration | 3. | Flash chamber |
D. | Jet refrigeration | 4. | Expansion cylinder |
A) A\[\to \]1, B\[\to \]4, C\[\to \]3, D\[\to \]2 done clear
B) A\[\to \]4, B\[\to \]1, C\[\to \]3, D\[\to \]2 done clear
C) A\[\to \]1, B\[\to \]4, C\[\to \]2, D\[\to \]3 done clear
D) A\[\to \]4, B\[\to \]1, C\[\to \]2, D\[\to \]3 done clear
View Solution play_arrowA) \[\frac{{{T}_{E}}({{T}_{G}}-{{T}_{C}})}{{{T}_{G}}({{T}_{C}}-{{T}_{E}})}\] done clear
B) \[\frac{{{T}_{G}}({{T}_{C}}-{{T}_{E}})}{{{T}_{E}}({{T}_{G}}-{{T}_{C}})}\] done clear
C) \[\frac{{{T}_{C}}({{T}_{G}}-{{T}_{E}})}{{{T}_{G}}({{T}_{C}}-{{T}_{E}})}\] done clear
D) \[\frac{{{T}_{G}}({{T}_{C}}-{{T}_{E}})}{{{T}_{C}}({{T}_{G}}-{{T}_{E}})}\] done clear
View Solution play_arrowquestion_answer103) In milk chilling plants, the usual secondary refrigerant is:
A) Ammonia solution done clear
B) Sodium Silicate done clear
C) Glycol done clear
D) Brine done clear
View Solution play_arrowquestion_answer104) 104. The desirable combination of properties of a refrigerant include :
A) High specific heat and low specific volume done clear
B) High heat transfer coefficient and low latent heat done clear
C) High thermal conductivity and low specific volume done clear
D) High specific heat and high boiling point. done clear
View Solution play_arrowquestion_answer105) Which of the following method(s) is/are adopted in the design of air duct system
1. Velocity reduction method |
2. Equal friction method |
3. Static regain method. |
A) 1 alone done clear
B) 1 and 2 done clear
C) 2 and 3 done clear
D) 1, 2 and 3 done clear
View Solution play_arrowA) Water vapour is in the superheated state done clear
B) The chart is for a given pressure done clear
C) The chart is an approximation to true values done clear
D) The mixtures can be treated as a perfect gas done clear
View Solution play_arrowquestion_answer107) During sensible cooling of air :
A) Its wet bulb temperature increases and dew point remains constant done clear
B) Its wet bulb temperature decreases and the dew point remains constant done clear
C) Its wet bulb temperature increases and the dew point decreases done clear
D) It wet bulb temperature decreases and dew point increases. done clear
View Solution play_arrowA) Relative humidity done clear
B) Specific humidity done clear
C) Degree of saturation done clear
D) Partial pressure done clear
View Solution play_arrowquestion_answer109) The effective temperature is a measure of the combined effects of:
A) Dry bulb temperature and relative humidity done clear
B) Dry bulb temperature and air motion done clear
C) Wet bulb temperature and air motion done clear
D) Dry bulb temperature, relative humidity and air motion. done clear
View Solution play_arrowA) Lower dry bulb temperature and lower relative humidity done clear
B) Lower dry bulb temperature and higher relative humidity done clear
C) Lower dry bulb temperature and same relative humidity done clear
D) Same dry bulb temperature and same relative humidity. done clear
View Solution play_arrowA) High and high done clear
B) High and low done clear
C) Low and high done clear
D) Low and low done clear
View Solution play_arrowA) Higher than the derived cold-region temperature and the condenser saturation temperature must be lower than the available cooling water temperature by sufficient amounts done clear
B) Low than the derived cold-region temperature and the condenser saturation temperature must be lower than the available cooling water temperature by sufficient amounts done clear
C) Lower than the derived cold-region temperature and the condenser saturation temperature must be higher than the available cooling water temperature by sufficient amounts done clear
D) Higher than the derived cold-region temperature and the condenser saturation temperature must he higher than the available cooling water temperature by sufficient amounts. done clear
View Solution play_arrowquestion_answer113) One ton refrigeration is equivalent to:
A) 3.5 kW done clear
B) 50 kJ/s done clear
C) 1000 J/min done clear
D) 1000 kJ/min done clear
View Solution play_arrowA) Evaporator, compressor, condenser and throttle valve done clear
B) Condenser, throttle valve, evaporator and compressor done clear
C) Compressor, condenser, throttle valve and evaporator done clear
D) Throttle valve, evaporator, compressor and condenser done clear
View Solution play_arrowA) 1.2 done clear
B) 1.25 done clear
C) 3.33 done clear
D) 4 done clear
View Solution play_arrowA) Liquid line done clear
B) Suction line done clear
C) Hot gas line done clear
D) Discharge line done clear
View Solution play_arrowquestion_answer117) A good refrigerant should have:
A) Large latent heat of vaporization and low operating pressures done clear
B) Small latent heat of vaporization and high operating pressures done clear
C) Large latent heat of vaporization and large operating pressures done clear
D) Small latent heat of vaporization and low operating pressures done clear
View Solution play_arrowA) Air-Water done clear
B) Lithium bromide-air done clear
C) Carbon dioxide-Water done clear
D) Ammonia-Water done clear
View Solution play_arrowquestion_answer119) Solar energy be directly used in:
A) Vapour compression refrigeration system done clear
B) Vapour absorption refrigeration system done clear
C) Air refrigeration system done clear
D) Jet refrigeration system done clear
View Solution play_arrowA) Relative humidity done clear
B) Degree of saturation done clear
C) Specific humidity done clear
D) Absolute humidity done clear
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