**Question 1: The lowest friction producing fluid film mechanism is **

A. Elasto-hydrodynamic lubrication. |

B. Hydrodynamic lubrication. |

C. Mixed lubrication. |

D. Boundary lubrication. |

**Question 2: Which one of following does not belong to equations required to estimate fluid film pressure? **

A. Reynolds’s equation. |

B. Bernoulli equation. |

C. Continuity equation. |

D. Navier Stokes equation. |

**Question 3: Petroff’s equation is used for **

A. Rough estimation of friction loss in sliding bearing. |

B. Change in viscosity wrt to temperature. |

C. Change in density wrt to temperature. |

D. Both (a) & (b). |

**Question 4: Which one of the following expressions represents the pressure term in Reynolds’s Equation for incompressible lubricants? **

A. |

B. |

C. |

D. |

**Question 5: Which equation is used to model the pressure distribution in elastohydrodynamic lubrication between spherical contacts? **

B. |

C. |

D. |

**Question 6: Which of the following equation is used to model the pressure distribution in elastohydrodynamic lubrication between cylindrical contacts? **

B. |

C. |

D. None of these |

**Question 7: The total applied load between spherical contacts in elastohydrodynamic lubrication can be calculated using the equation : **

B. |

C. |

D. |

**Question 8: The total applied load between cylindrical contacts in elastohydrodynamic lubrication can be calculated using the equation : **

B. |

C. |

D. |

**Question 9: To calculate the total applied load between spherical and cylindrical contacts in elastohydrodynamic lubrication, the elastic deformation as suggested by Timoshenko & Goodiercan be calculated using the equation : **

B. |

C. |

D. |

**Question 10: Load capacity of cylindrical contact compared to spherical contact is :
**

A. Higher. |

B. Smaller. |

C. Similar. |

D. Cannot be compared without specifying dimensions. |

**Question 11: Due to elastic deformation along the contact patch in elastohydrodynamic lubrication, the maximum value of the pressure : **

A. Increases. |

B. Decreases. |

C. Remains same. |

D. Cannot be said. |

**Question 12: Thermohydrodynamic lubrication is referred as : **

A. Hydrodynamic lubrication with allowance for viscous heating. |

B. Lubrication mechanism which does not allow viscous heating. |

C. Hydrodynamic lubrication in which heating of the lubricant cannot occur. |

D. None of these. |

**Question 13: In journal bearing, friction loss can be represented as : **

B. |

C. |

D. |

**Question 14: Which among the following represent the value of Φ for Newtonian fluid in the energyequation? **

B. |

C. |

D. |

**Question 15: For practical purposes the friction force in hydrodynamic lubrication is represented as : **

A. |

B. |

C. |

D. |

**Question 16: Which of the fluid film lubrication mechanism is suitable for very high loads moving at low speeds like large telescopes, radar tracking units, machine tools and gyroscopes? **

A. Hydrodynamic lubrication. |

B. Hydrostatic lubrication. |

C. Squeeze film lubrication. |

D. Aerostatic lubrication. |

**Question 17: In hydrodynamic lubrication minimum film thickness (h _{min}), a critical design criterion, is a function of : **

A. Relative velocity (U). |

B. Applied load (W). |

C. Viscosity. |

D. All of above. |