A full journal bearing having clearance to radius ratio of 1/100, using a lubricant with μ=28×10-3 Pa s supports the shaft journal running at N = 2400 rpm If bearing pressure is 1.4 MPa, the Somerfield number is [IES-2001] (a) 8×10-3 (b) 8×10-5 (c) 0.48 (d) 0.48×10

A full journal bearing having clearance to radius ratio of 1/100, using a lubricant with μ=28×10-3 Pa s supports the

shaft journal running at N = 2400 rpm If bearing pressure is 1.4 MPa, the Somerfield number is [IES-2001]

(a) 8×10-3 (b) 8×10-5 (c) 0.48 (d) 0.48×10
by

1 Answer

Answer :

(a) S = (μN s /p) (r/c) 2
by

Related questions

Satisfactory hydrodynamic film in a journal bearing is formed when (a) Journal speed is low; unit pressure on the bearing is high and viscosity of lubricant used is low [IES-2006] (b) Journal speed is low; unit pressure on the bearing is low and viscosity of lubricant used is low (c) Journal speed is high; unit pressure on the bearing is high and viscosity of lubricant used is high (d) Appropriate combination of journal speed, unit pressure on bearing and lubricant viscosity exists resulting in low coefficient of friction

Description : Satisfactory hydrodynamic film in a journal bearing is formed when (a) Journal speed is low; unit pressure on the bearing is high and viscosity of lubricant used is low [IES-2006] ... journal speed, unit pressure on bearing and lubricant viscosity exists resulting in low coefficient of friction

Last Answer : (c) Journal speed is high; unit pressure on the bearing is high and viscosity of lubricant used is high

Consider the following statements: [IES 2007] For a journal rotating in a bearing under film lubrication conditions, the frictional resistance is- 1. Proportional to the area of contact 2. Proportional to the viscosity of lubricant 3. Proportional to the speed of rotation 4. Independent of the pressure Which of the statements given above are correct? (a) 1, 2, 3 and 4 (b) 1 and 4 only (c) 2, 3 and 4 only (d) 2 and 3 only

Description : Consider the following statements: [IES 2007] For a journal rotating in a bearing under film lubrication conditions, the frictional resistance is- 1. Proportional to the area of contact 2. Proportional to the viscosity of lubricant 3. ... 4 (b) 1 and 4 only (c) 2, 3 and 4 only (d) 2 and 3 only

Last Answer : (a) 1, 2, 3 and 4

Consider tile following statements: [IES-1993; 2002; 2006] Radius of friction circle for a journal bearing depends upon 1. Coefficient of friction 2. Radius of the journal 3. Angular speed of rotation of the shaft Which of the statements given above are correct? (a) 1,2 and 3 (b) Only 1 and 2 (c) Only 2 and 3 (d) Only 1 and 3

Description : Consider tile following statements: [IES-1993; 2002; 2006] Radius of friction circle for a journal bearing depends upon 1. Coefficient of friction 2. Radius of the journal 3. Angular speed of rotation of the shaft Which of the ... ) 1,2 and 3 (b) Only 1 and 2 (c) Only 2 and 3 (d) Only 1 and 3

Last Answer : (b) Only 1 and 2

Which one of the following pair is correctly matched? [IES-2000] (a) Beauchamp tower ........................First experiments on journal bearings (b) Osborne Reynolds ........................Antifriction bearings (c) Somerfield number........................Pivot and Collar bearings (d) Ball bearings...............................Hydrodynamic lubrication

Description : Which one of the following pair is correctly matched? [IES-2000] (a) Beauchamp tower ........................First experiments on journal bearings (b) Osborne Reynolds ........................ ... .Pivot and Collar bearings (d) Ball bearings...............................Hydrodynamic lubrication

Last Answer : (a) Beauchamp tower ........................First experiments on journal bearings

For elasto-hydrodynamic lubrication (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space (B) There should be external source like pump to supply lubricant under pressure (C) There should be elastic deformation of the parts in contact (D) There should be metal to metal contact

Description : For elasto-hydrodynamic lubrication (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space (B) There should be external source like ... be elastic deformation of the parts in contact (D) There should be metal to metal contact

Last Answer : (C) There should be elastic deformation of the parts in contact

For hydrostatic lubrication (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space (B) There should be external source like pump to supply lubricant under pressure (C) There should be elastic deformation of the parts in contact (D) There should be metal to metal contact

Description : For hydrostatic lubrication (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space (B) There should be external source like pump to ... be elastic deformation of the parts in contact (D) There should be metal to metal contact

Last Answer : (B) There should be external source like pump to supply lubricant under pressure

For hydrodynamic lubrication (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space (B) There should be external source like pump to supply lubricant under pressure (C) There should be elastic deformation of the parts in contact (D) There should be metal to metal contact

Description : For hydrodynamic lubrication (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space (B) There should be external source like pump to ... be elastic deformation of the parts in contact (D) There should be metal to metal contact

Last Answer : (A) There should be relative motion between the surfaces of the journal and the bearing and wedge shaped clearance space

In a journal bearings, the radius of the friction circle increases with the increase in- [IES-1997] (a) Load (b) Radius of the journal (c) Speed of the journal (d) Viscosity of the lubricant

Description : In a journal bearings, the radius of the friction circle increases with the increase in- [IES-1997] (a) Load (b) Radius of the journal (c) Speed of the journal (d) Viscosity of the lubricant

Last Answer : (b) Radius of the journal

Which one of the following sets of parameters should be monitored for determining safe operation of journal bearing? [IES-2000] Oil pressure, bearing metal temperature and bearing vibration (b) Bearing vibration, oil pressure and speed of shaft (c) Bearing metal temperature and oil pressure (d) Oil pressure and bearing vibration

Description : Which one of the following sets of parameters should be monitored for determining safe operation of journal bearing? [IES-2000] Oil pressure, bearing metal temperature and bearing vibration (b) ... shaft (c) Bearing metal temperature and oil pressure (d) Oil pressure and bearing vibration

Last Answer : Oil pressure, bearing metal temperature and bearing vibration

Consider the following pairs of types of bearings and applications: 1. Partial Journal bearing................... Rail wagon axles 2. Full journal bearing ......................Diesel engine crank-shaft 3. Radial bearing ............................Combined radial and axial loads Which of these pairs is/are correctly matched? [IES-2000] (a) 1 alone (b) 1 and 2 (c) 2 and 3 (d) 1, 2 and 3

Description : Consider the following pairs of types of bearings and applications: 1. Partial Journal bearing................... Rail wagon axles 2. Full journal bearing ......................Diesel engine crank-shaft 3. Radial bearing ... matched? [IES-2000] (a) 1 alone (b) 1 and 2 (c) 2 and 3 (d) 1, 2 and 3

Last Answer : (b) 1 and 2

Increase in values of which of the following results in an increase of the coefficient of friction in a hydrodynamic bearing? [IES 2007] 1. Viscosity of the oil. 2. Clearance between shaft and bearing. 3. Shaft speed. Select the using the code given below: (a) 1 and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1, 2 and 3

Description : Increase in values of which of the following results in an increase of the coefficient of friction in a hydrodynamic bearing? [IES 2007] 1. Viscosity of the oil. 2. Clearance between shaft and bearing. 3. Shaft speed. Select the ... 1 and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1, 2 and 3

Last Answer : (b) 1 and 3 only

If μ = absolute viscosity, N= speed of the journal and p = unit bearing pressure, then the bearing characteristic number is given by (A) μN/p (B) μp/N (C) pN/μ (D) μ/pN

Description : If μ = absolute viscosity, N= speed of the journal and p = unit bearing pressure, then the bearing characteristic number is given by (A) μN/p (B) μp/N (C) pN/μ (D) μ/pN

Last Answer : (A) μN/p

Assertion (A): In hydrodynamic journal bearings, the rotating journal is held in floating condition by the hydrodynamic pressure developed in the lubricant. Reason (R): Lubricant flows in a converging-diverging channel. [IES-1994] (a) Both A and R are individually true and R is the correct explanation of A (b) Both A and R are individually true but R is not the correct explanation of A (c) A is true but R is false (d) A is false but R is true

Description : Assertion (A): In hydrodynamic journal bearings, the rotating journal is held in floating condition by the hydrodynamic pressure developed in the lubricant. Reason (R): Lubricant flows in a converging-diverging channel. [IES-1994] ... A (c) A is true but R is false (d) A is false but R is true

Last Answer : (a) Both A and R are individually true and R is the correct explanation of A

A journal bearing with hydrodynamic lubrication is running steadily with a certain amount of minimum film thickness. When the load and speed are doubled, how does the minimum film thickness vary? [IES-2008] (a) Remains unchanged (b) Gets doubled (c) Gets reduced to one-fourth of original value (d) Gets reduced to half of original value

Description : A journal bearing with hydrodynamic lubrication is running steadily with a certain amount of minimum film thickness. When the load and speed are doubled, how does the minimum film thickness vary? [IES-2008 ... Gets reduced to one-fourth of original value (d) Gets reduced to half of original value

Last Answer : (a) Remains unchanged

A clearance bearing is design accurately to keep the radius of journal and bearing equal. a) Journal radius is kept larger b) Journal radius is kept smaller c) True d) Can’t be determined

Description : A clearance bearing is design accurately to keep the radius of journal and bearing equal. a) Journal radius is kept larger b) Journal radius is kept smaller c) True d) Can’t be determined

Last Answer : b) Journal radius is kept smaller

Assertion (A): Hydrostatic lubrication is more advantageous when compared to hydrodynamic lubrication during starting and stopping the journal in its bearing. Reason (R): In hydrodynamic lubrication, the fluid film pressure is generated by the rotation of the journal. [IES-1998] (a) Both A and R are individually true and R is the correct explanation of A (b) Both A and R are individually true but R is not the correct explanation of A (c) A is true but R is false (d) A is false but R is true

Description : Assertion (A): Hydrostatic lubrication is more advantageous when compared to hydrodynamic lubrication during starting and stopping the journal in its bearing. Reason (R): In hydrodynamic lubrication, the fluid film pressure is ... (c) A is true but R is false (d) A is false but R is true

Last Answer : (b) Both A and R are individually true but R is not the correct explanation of A

Assertion (A): In steady rotating condition the journal inside a hydrodynamic journal bearing remains floating on the oil film. [IES-2008] Reason (R): The hydrodynamic pressure developed in steady rotating conditions in journal bearings balances the load on the journal. (a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true but R is NOT the correct explanation of A (c) A is true but R is false (d) A is false but R is true

Description : Assertion (A): In steady rotating condition the journal inside a hydrodynamic journal bearing remains floating on the oil film. [IES-2008] Reason (R): The hydrodynamic pressure developed in steady rotating conditions in journal ... A (c) A is true but R is false (d) A is false but R is true

Last Answer : (a) Both A and R are true and R is the correct explanation of A

Match List I with List II and select the : [IES-2002] List I (Bearings) List II (Load type) A. Hydrodynamic Journal bearing 1. High radial and thrust load combined B. Rectangular Hydrostatic bearing 2. Radial load only C. Taper Roller bearing 3. Thrust load only D. Angular contact ball bearing 4. Medium to low radial and thrust combined A B C D A B C D (a) 2 3 1 4 (b) 4 1 3 2 (c) 2 1 3 4 (d) 4 3 1 2

Description : Match List I with List II and select the : [IES-2002] List I (Bearings) List II (Load type) A. Hydrodynamic Journal bearing 1. High radial and thrust load combined B. Rectangular Hydrostatic bearing 2. Radial load only C. Taper Roller ... (a) 2 3 1 4 (b) 4 1 3 2 (c) 2 1 3 4 (d) 4 3 1 2

Last Answer : (a) 2 3 1 4

In an oil-lubricated journal bearing, coefficient of friction between the journal and the bearing. [IES-1995] (a) Remains constant at all speeds. (b) is minimum at zero speed and increases monotonically with increase in speed. (c) is maximum at zero speed and decreases monotonically with increase in speed. (d) becomes minimum at an optimum speed and then increases with further increase in speed.

Description : In an oil-lubricated journal bearing, coefficient of friction between the journal and the bearing. [IES-1995] (a) Remains constant at all speeds. (b) is minimum at zero speed and increases ... speed. (d) becomes minimum at an optimum speed and then increases with further increase in speed.

Last Answer : (d) becomes minimum at an optimum speed and then increases with further increase in speed.

Assertion (A): In equilibrium position, the journal inside a journal bearing remains floating on the oil film. [IES-1995] Reason (R): In a journal bearing, the load on the bearing is perpendicular to the axis of the journal. (a) Both A and R are individually true and R is the correct explanation of A (b) Both A and R are individually true but R is not the correct explanation of A (c) A is true but R is false (d) A is false but R is true

Description : Assertion (A): In equilibrium position, the journal inside a journal bearing remains floating on the oil film. [IES-1995] Reason (R): In a journal bearing, the load on the bearing is perpendicular to the axis of the ... explanation of A (c) A is true but R is false (d) A is false but R is true

Last Answer : (b) Both A and R are individually true but R is not the correct explanation of A

A thick film bearing is a bearing (A) Where the surfaces of journal and the bearing are completely separated by a film of lubricant (B) Where the surfaces of journal and the bearing are partially separated by a film of lubricant and there is partial metal to metal contact (C) Where the surfaces of journal and the bearing are separated by a film created by elastic deflection of parts (D) Where there is no lubricant

Description : A thick film bearing is a bearing (A) Where the surfaces of journal and the bearing are completely separated by a film of lubricant (B) Where the surfaces of journal and the bearing are partially ... are separated by a film created by elastic deflection of parts (D) Where there is no lubricant

Last Answer : (A) Where the surfaces of journal and the bearing are completely separated by a film of lubricant

A thin film bearing is a bearing (A) Where the surfaces of journal and the bearing are completely separated by a film of lubricant (B) Where the surfaces of journal and the bearing are partially separated by a film of lubricant and there is partial metal to metal contact (C) Where the surfaces of journal and the bearing are separated by a film created by elastic deflection of parts (D) Where there is no lubricant

Description : A thin film bearing is a bearing (A) Where the surfaces of journal and the bearing are completely separated by a film of lubricant (B) Where the surfaces of journal and the bearing are partially ... are separated by a film created by elastic deflection of parts (D) Where there is no lubricant

Last Answer : (B) Where the surfaces of journal and the bearing are partially separated by a film of lubricant and there is partial metal to metal contact

A zero film bearing is a bearing (A) Where the surfaces of journal and the bearing are separated by a thick film of lubricant (B) Where the surfaces of journal and the bearing are partially separated by a film of lubricant and there is partial metal to metal contact (C) Where the surfaces of journal and the bearing are separated by a film created by elastic deflection of parts (D) Where there is no lubricant

Description : A zero film bearing is a bearing (A) Where the surfaces of journal and the bearing are separated by a thick film of lubricant (B) Where the surfaces of journal and the bearing are partially ... bearing are separated by a film created by elastic deflection of parts (D) Where there is no lubricant

Last Answer : (D) Where there is no lubricant

The static load is defined as the load acting on the bearing when the shaft is _____. (a) stationary (b) rotating at rpm<5 (c) rotating at rpm<10 (d) rotating at rpm<15

Description : The static load is defined as the load acting on the bearing when the shaft is _____. (a) stationary (b) rotating at rpm

Last Answer : (a) stationary

Static load is defined as the load acting on the bearing when shaft is _____ a) Stationary b) Rotating at rpm<10 c) Rotating at rpm<5 d) None of the listed

Description : Static load is defined as the load acting on the bearing when shaft is _____ a) Stationary b) Rotating at rpm

Last Answer : a) Stationary

A journal bearing is a ______ contact bearing working on the hydrodynamic lubrication and which supports load in____ direction. a) Sliding, Axial b) Rolling, Radial c) Sliding, Radial d) Rolling, Axial

Description : A journal bearing is a ______ contact bearing working on the hydrodynamic lubrication and which supports load in____ direction. a) Sliding, Axial b) Rolling, Radial c) Sliding, Radial d) Rolling, Axial

Last Answer : c) Sliding, Radial

Calculate the bearing life if expected life for 90% bearings is 9000 hr and the shaft is rotating at 1500 rpm. (a) 850 million rev (b) 810 million rev (c) 810 hr (d) 850 hr

Description : Calculate the bearing life if expected life for 90% bearings is 9000 hr and the shaft is rotating at 1500 rpm. (a) 850 million rev (b) 810 million rev (c) 810 hr (d) 850 hr

Last Answer : (b) 810 million rev

In hydrodynamic bearing, when the shaft begins to rotate in clockwise direction, (A) The journal climbs to the right side of the bearing without metal to metal contact (B) The journal climbs to the left side of the bearing without metal to metal contact (C) The journal sinks down to the bottom of the bearing (D) The journal is at the center of the bearing

Description : In hydrodynamic bearing, when the shaft begins to rotate in clockwise direction, (A) The journal climbs to the right side of the bearing without metal to metal contact (B) The journal climbs to the left ... sinks down to the bottom of the bearing (D) The journal is at the center of the bearing

Last Answer : (A) The journal climbs to the right side of the bearing without metal to metal contact

A_______ bearing supports the load acting along the axis of the shaft. a) Thrust b) Radial c) Longitudinal d) Transversal

Description : A_______ bearing supports the load acting along the axis of the shaft. a) Thrust b) Radial c) Longitudinal d) Transversal

Last Answer : a) Thrust

A radial bearing supports the load that acts along the axis of the shaft. a) True b) False

Description : A radial bearing supports the load that acts along the axis of the shaft. a) True b) False

Last Answer : b) False

In hydrostatic bearings (A) The Oil film pressure is generated only by the rotation of the journal (B) The oil film is maintained by supplying oil under pressure (C) Do not require external supply of lubricant (D) Grease is used for lubrication

Description : In hydrostatic bearings (A) The Oil film pressure is generated only by the rotation of the journal (B) The oil film is maintained by supplying oil under pressure (C) Do not require external supply of lubricant (D) Grease is used for lubrication

Last Answer : (B) The oil film is maintained by supplying oil under pressure

The bearing characteristic number in a hydrodynamic bearing depends on- (a) Length, width and load (b) length, width and speed. [IES-1996] (c) Viscosity, speed and load (d) viscosity, speed and bearing pressure.

Description : The bearing characteristic number in a hydrodynamic bearing depends on- (a) Length, width and load (b) length, width and speed. [IES-1996] (c) Viscosity, speed and load (d) viscosity, speed and bearing pressure.

Last Answer : (d) viscosity, speed and bearing pressure.

A shaft turns at 150 rpm under a torque of 1500 N-m. Power transmitted is (a) 15p kW (b) 10p kW (c) 7.5p kW (d) 5p kW (IES 1999) Hint: P = 2pNT/60

Description : A shaft turns at 150 rpm under a torque of 1500 N-m. Power transmitted is (a) 15p kW (b) 10p kW (c) 7.5p kW (d) 5p kW (IES 1999) Hint: P = 2pNT/60

Last Answer : (c) 7.5p kW

Which one of the following types of bearings is employed in shafts of gearboxes of automobiles? [IES-1999] (a) Hydrodynamic journal bearings (b) Multi-lobed journal bearings (c) Antifriction bearings (d) Hybrid journal bearings

Description : Which one of the following types of bearings is employed in shafts of gearboxes of automobiles? [IES-1999] (a) Hydrodynamic journal bearings (b) Multi-lobed journal bearings (c) Antifriction bearings (d) Hybrid journal bearings

Last Answer : (c) Antifriction bearings

Match List-I (Type of Anti-friction bearing) with List-II (Specific Use) and select the using the code given below the Lists: [IES-2006] List-I List -II A. Self-aligning ball bearing 1. For pure axial load B. Taper roller bearing 2. For hinged condition C. Deep groove ball bearing 3. For pure radial load D. Thrust ball bearing 4. For axial and radial load A B C D A B C D (a) 2 1 3 4 (b) 3 4 2 1 (c) 2 4 3 1 (d) 3 1 2 4

Description : Match List-I (Type of Anti-friction bearing) with List-II (Specific Use) and select the using the code given below the Lists: [IES-2006] List-I List -II A. Self-aligning ball bearing 1. For pure axial load B. Taper roller bearing 2. For ... C D (a) 2 1 3 4 (b) 3 4 2 1 (c) 2 4 3 1 (d) 3 1 2 4

Last Answer : (c) 2 4 3 1

Which of the following are included in the finishing operations for porous bearing? [IES-2005] 1. Infiltration 2.Sizing 3.Heat treatment 4.Coining Select the using the code given below: (a) 1 and 2 (b) 2 and 3 (c) 2 and 4 (d) 1 and 4

Description : Which of the following are included in the finishing operations for porous bearing? [IES-2005] 1. Infiltration 2.Sizing 3.Heat treatment 4.Coining Select the using the code given below: (a) 1 and 2 (b) 2 and 3 (c) 2 and 4 (d) 1 and 4

Last Answer : (a) 1 and 2

A spring of stiffness 100 N/mm used in a spring-loaded safety valve of diameter 20 mm on a boiler with the pressure inside the boiler equal to 1 MPa should be initially compressed by a. 5mm b. 3.14 mm c. 2mm d. 6.28 mm

Description : A spring of stiffness 100 N/mm used in a spring-loaded safety valve of diameter 20 mm on a boiler with the pressure inside the boiler equal to 1 MPa should be initially compressed by a. 5mm b. 3.14 mm c. 2mm d. 6.28 mm

Last Answer : b. 3.14 mm

What is the main advantage of hydrodynamic bearing over roller bearing? (a) Easy to assemble [IES-2005] (b) Relatively low price (c) Superior load carrying capacity at higher speeds (d) Less frictional resistance

Description : What is the main advantage of hydrodynamic bearing over roller bearing? (a) Easy to assemble [IES-2005] (b) Relatively low price (c) Superior load carrying capacity at higher speeds (d) Less frictional resistance

Last Answer : (c) Superior load carrying capacity at higher speeds

Which one of the following is correct? [IES-2008] A hydrodynamic slider bearing develops load bearing capacity mainly because of- (a) Slider velocity (b) wedge shaped oil film (c) Oil compressibility (d) oil viscosity

Description : Which one of the following is correct? [IES-2008] A hydrodynamic slider bearing develops load bearing capacity mainly because of- (a) Slider velocity (b) wedge shaped oil film (c) Oil compressibility (d) oil viscosity

Last Answer : (b) wedge shaped oil film

Petroff’s equation is used to find out (A) Load carrying capacity of the bearing (B) Frictional losses in the bearing (C) Unit bearing pressure on the bearing (D) Pressure distribution around the periphery of the journal

Description : Petroff’s equation is used to find out (A) Load carrying capacity of the bearing (B) Frictional losses in the bearing (C) Unit bearing pressure on the bearing (D) Pressure distribution around the periphery of the journal

Last Answer : (B) Frictional losses in the bearing

Match List -I (Bearings) with List-II (Applications) and select the using the codes given below the lists: [IAS-1998] List –I List-II A. Journal bearing 1. Electric motors B. Thrust bearing 2. Watches C. Conical pivot bearing 3. Marine engines D. Ball bearing 4. Swivelling chairs A B C D A B C D (a) 3 4 1 2 (b) 4 2 1 3 (c) 3 4 2 1 (d) 4 2 3 1

Description : Match List -I (Bearings) with List-II (Applications) and select the using the codes given below the lists: [IAS-1998] List -I List-II A. Journal bearing 1. Electric motors B. Thrust bearing 2. Watches C. Conical pivot bearing 3. Marine ... D (a) 3 4 1 2 (b) 4 2 1 3 (c) 3 4 2 1 (d) 4 2 3 1

Last Answer : (c) 3 4 2 1

_______is suitable as a lubricant for heavy-duty applications of rolling contact bearing. (a) Grease (b) Lubricating oil (c) Graphite (d) Air

Description : _______is suitable as a lubricant for heavy-duty applications of rolling contact bearing. (a) Grease (b) Lubricating oil (c) Graphite (d) Air

Last Answer : (b) Lubricating oil

________is suitable as a lubricant for low and moderate loads applications of rolling contact bearing. (a) Grease (b) Lubricating oil (c) Graphite (d) Air

Description : ________is suitable as a lubricant for low and moderate loads applications of rolling contact bearing. (a) Grease (b) Lubricating oil (c) Graphite (d) Air

Last Answer : (a) Grease

The ball bearing is subjected to a radial load of 4000 N. Expected life for 90% bearings is 9000 hr and the shaft is rot (a) 42.21 kN (b) 37.29 kN (c) 26.33 kN (d) 35.22 kN

Description : The ball bearing is subjected to a radial load of 4000 N. Expected life for 90% bearings is 9000 hr and the shaft is rot (a) 42.21 kN (b) 37.29 kN (c) 26.33 kN (d) 35.22 kN

Last Answer : (b) 37.29 kN

A lubricant 100 times more viscous than water would have a viscosity (in Pa.s) (A) 0.01 (B) 0.1 (C) 1 (D) 10

Description : A lubricant 100 times more viscous than water would have a viscosity (in Pa.s) (A) 0.01 (B) 0.1 (C) 1 (D) 10

Last Answer : (B) 0.1

In case of full journal bearing, the angle of contact of the bushing with the journal is (A) 60° (B) 90° (C) 180° (D) 360°

Description : In case of full journal bearing, the angle of contact of the bushing with the journal is (A) 60° (B) 90° (C) 180° (D) 360°

Last Answer : (D) 360°

A hollow shaft has an inner diameter of 3.7 cm and an outer diameter of 4.0 cm. A 1 kN-m torque is applied to this shaft. What is the shear stress at the mid-radius of this shaft? (a) 117Mpa (b) 178 Mpa (c) 286 Mpa (d) 363 Mpa

Description : A hollow shaft has an inner diameter of 3.7 cm and an outer diameter of 4.0 cm. A 1 kN-m torque is applied to this shaft. What is the shear stress at the mid-radius of this shaft? (a) 117Mpa (b) 178 Mpa (c) 286 Mpa (d) 363 Mpa

Last Answer : (c) 286 Mpa

What is the value of shear stress acting on a plane of circular bar which is subjected to axial tensile load of 100 kN? (Diamet a. 58.73 Mpa b. 40.23 Mpa c. 39.60 Mpa d. Insufficient data

Description : What is the value of shear stress acting on a plane of circular bar which is subjected to axial tensile load of 100 kN? (Diamet a. 58.73 Mpa b. 40.23 Mpa c. 39.60 Mpa d. Insufficient data

Last Answer : c. 39.60 Mpa