The best lubricants for a machine working at high temperature & load is (A) Grease (B) Solid lubricant (C) Animal oils (D) Mineral oils

The best lubricants for a machine working at high temperature & load
is
(A) Grease
(B) Solid lubricant
(C) Animal oils
(D) Mineral oils
by

1 Answer

Answer :

Option B
by

Related questions

Mineral oils (e.g. petroleum oils) are preferred over fatty oils (e.g. mustard oil, ghee, tallow, palm oil, olive oil etc.) as a lubricant due to its (A) Poor oxidation stability and high gum forming tendency (B) Greater tendency of decomposition at elevated temperature (C) Hydrolysis tendency in presence of water (D) All (A), (B) and (C)

Description : Mineral oils (e.g. petroleum oils) are preferred over fatty oils (e.g. mustard oil, ghee, tallow, palm oil, olive oil etc.) as a lubricant due to its (A) Poor oxidation stability and high gum forming ... at elevated temperature (C) Hydrolysis tendency in presence of water (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Silicone resins, which are highly water repellent and has good heat resistance cannot be used (A) As room temperature adhesive (B) As grease & lubricant

Description : Silicone resins, which are highly water repellent and has good heat resistance cannot be used (A) As room temperature adhesive (B) As grease & lubricant

Last Answer : (A) As room temperature adhesive

Define lubricant. Give the classification of lubricants with at least one example of each type.

Description : Define lubricant. Give the classification of lubricants with at least one example of each type.

Last Answer : Lubricant: Any substance introduced between two moving or sliding surface to reduce the frictional resistance between them is known as lubricant. Classification: i) Solid lubricants: Examples: graphite, ... acids like oleic acid, Stearic acid etc., silicones, blended oils, and mineral oils.

_______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

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

Pick out the correct combination about the role of various additives used in polymers. (A) Plasticiser: increases the polymer strength (B) Heat stabiliser: increases the maximum service temperature (C) Fillers: Does not affect the property of polymer but increases its weight (D) Lubricants: increases the flexibility of polymers

Description : Pick out the correct combination about the role of various additives used in polymers. (A) Plasticiser: increases the polymer strength (B) Heat stabiliser: increases the maximum service ... property of polymer but increases its weight (D) Lubricants: increases the flexibility of polymers

Last Answer : Option C

What Designed to regulate temperature secrete lubricants and protect the body from harmful substances?

Description : What Designed to regulate temperature secrete lubricants and protect the body from harmful substances?

Last Answer : Epithelial tissues

Babbitt metal used for making bearings should have (A) High co-efficient of friction between journal and bearing (B) Ability to retain lubricant on its surface (C) Low co-efficient of friction between journal and bearing (D) Both (B) & (C)

Description : Babbitt metal used for making bearings should have (A) High co-efficient of friction between journal and bearing (B) Ability to retain lubricant on its surface (C) Low co-efficient of friction between journal and bearing (D) Both (B) & (C)

Last Answer : (A) High co-efficient of friction between journal and bearing

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

Suggest the type of lubricant used for the following jobs: i) Clock ii) I.C. Engines iii) Gears iv) Sewing machine

Description : Suggest the type of lubricant used for the following jobs: i) Clock ii) I.C. Engines iii) Gears iv) Sewing machine

Last Answer : i) Clock : Vegetable and animal oils like palm oil, hazel nut oil, neat foot oil, etc ii) I.C. Engines: Mineral oils containing additives are used. iii) Gears: Thick mineral oils containing ... Mineral oil, silicones, thin vegetable and animal oils like palm oil, hazel nut oil, neat foot oil.

What are the types of lubricants ?

Description : What are the types of lubricants ?

Last Answer : Lubricants can be classified as follows. Namely- (a) Mineral oil. (B) Animal and plant oils (c) Synthetic oils (d) Other liquids (e) Grease (f) Solid lubricants.

How many types of lubricants according to the source ?

Description : How many types of lubricants according to the source ?

Last Answer : : According to the source, there are 2 types of lubricants. For example: animals and plants.

Explain how lubricants help in reducing friction?

Description : Explain how lubricants help in reducing friction?

Last Answer : Explain how lubricants help in reducing friction?

Volatile hydrocarbons are not used in the brakes of automobile as lubricants, but non-volatile hydrocarbons are used as lubricants.

Description : Volatile hydrocarbons are not used in the brakes of automobile as lubricants, but non-volatile hydrocarbons are used as lubricants.

Last Answer : Ans.: The vapour pressure of volatile hydrocarbons is very high and they get evaporated leaving behind the system. Due to this they are not used as lubricants in automobiles. Nonvolatile hydrocarbons having low vapour pressure are used as lubricants.

Sun Petroleum Products departmentalizes by fuels, lubricants, and waxes and chemicals. This is an example of departmentalization by……….. (a) Product ; (b) Functions ; (c) Job design ; (d) Customer

Description : Sun Petroleum Products departmentalizes by fuels, lubricants, and waxes and chemicals. This is an example of departmentalization by……….. (a) Product ; (b) Functions ; (c) Job design ; (d) Customer

Last Answer : (a) Product ;

Define lubricants. Gives its types.

Description : Define lubricants. Gives its types.

Last Answer : Lubricant:- Any substance introduced between two moving or sliding surfaces to reduce the frictional resistance between them is known as a lubricant. Types of Lubricant:- i) Solid lubricant ii) Semi-solid lubricant iii) Liquid lubricant.

Under normal operating conditions, the bearings are filled with the proper type of lubricant after every hours of working about a) 6 hours b) 8 hoursc) 10 hours d) 12 hours

Description : Under normal operating conditions, the bearings are filled with the proper type of lubricant after every hours of working about a) 6 hours b) 8 hoursc) 10 hours d) 12 hours

Last Answer : c) 10 hours

Viscosity index improver (like polystyrene or polyisobutylene) is added to lubricant to (A) Reduce its viscosity (B) Increase its viscosity (C) Reduce the variation in its viscosity with temperature(D) Increase the variation in its viscosity with temperature

Description : Viscosity index improver (like polystyrene or polyisobutylene) is added to lubricant to (A) Reduce its viscosity (B) Increase its viscosity (C) Reduce the variation in its viscosity with temperature (D) Increase the variation in its viscosity with temperature

Last Answer : (C) Reduce the variation in its viscosity with temperature

__________ of a material results, when its strength is increased & ductility is decreased by heating at a relatively lower temperature after cold working. (A) Solid solution hardening (B) Screw dislocation (C) Strain ageing (D) Twinning

Description : __________ of a material results, when its strength is increased & ductility is decreased by heating at a relatively lower temperature after cold working. (A) Solid solution hardening (B) Screw dislocation (C) Strain ageing (D) Twinning

Last Answer : (C) Strain ageing

Vegetable oils are converted into solid fat (ghee) by - (1) Hydrolysis (2) Addition of agar (3) Oxidation using air and a catalyst (4) Hydrogenation

Description : Vegetable oils are converted into solid fat (ghee) by - (1) Hydrolysis (2) Addition of agar (3) Oxidation using air and a catalyst (4) Hydrogenation

Last Answer : (4) Hydrogenation Explanation: Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a ... oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).

Liquid oils can be converted to solid fats by (a) Hydrogenation (b) Saponification (c) Hydrolysis (d) Oxidation of double bonds

Description : Liquid oils can be converted to solid fats by (a) Hydrogenation (b) Saponification (c) Hydrolysis (d) Oxidation of double bonds

Last Answer : Hydrogenation

Vegetable oils are converted into solid fat (ghee) by (1) Hydrolysis (2) Addition of agar (3) Oxidation using air and a catalyst (4) Hydrogenation

Description : Vegetable oils are converted into solid fat (ghee) by (1) Hydrolysis (2) Addition of agar (3) Oxidation using air and a catalyst (4) Hydrogenation 

Last Answer : Hydrogenation

Crude oil is subjected to vacuum distillation in the last stage, because (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose (B) Lighter/low boiling products are prone to thermal decomposition (C) High purity products can be obtained thereby (D) None of these

Description : Crude oil is subjected to vacuum distillation in the last stage, because (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose (B) Lighter/low ... prone to thermal decomposition (C) High purity products can be obtained thereby (D) None of these

Last Answer : (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose

. Pick out the wrong statement. (A) Multigrade lubricating oils have high viscosity index (B) Paraffinic oil has very high viscosity index (C) Naphthenic oil has very low viscosity index (D) High viscosity index means a large change in viscosity with change in temperature

Description : . Pick out the wrong statement. (A) Multigrade lubricating oils have high viscosity index (B) Paraffinic oil has very high viscosity index (C) Naphthenic oil has very low viscosity index (D) High viscosity index means a large change in viscosity with change in temperature

Last Answer : (D) High viscosity index means a large change in viscosity with change in temperature

Preheating before welding is done to (A) Make the plate softer (B) Burn oil & grease sticking to plate surfaces (C) Avoid plate distortion (D) Prevent cold cracks

Description : Preheating before welding is done to (A) Make the plate softer (B) Burn oil & grease sticking to plate surfaces (C) Avoid plate distortion (D) Prevent cold cracks

Last Answer : (D) Prevent cold cracks

Tractor engine oil should be changed and all grease points should be lubricated after every working hrs 1. 15 2. 30 3. 60 4. 120

Description : Tractor engine oil should be changed and all grease points should be lubricated after every working hrs 1. 15 2. 30 3. 60 4. 120

Last Answer : ans 4

Penetration test determines the __________ of the grease. (A) Stiffness (B) Lubricating properties (e.g. oilness) (C) Service temperature (D) Variation in viscosity with temperature

Description : Penetration test determines the __________ of the grease. (A) Stiffness (B) Lubricating properties (e.g. oilness) (C) Service temperature (D) Variation in viscosity with temperature

Last Answer : (A) Stiffness

A good lubricant should have high (A) Viscosity index (B) Volatility (C) Pour point (D) None of these

Description : A good lubricant should have high (A) Viscosity index (B) Volatility (C) Pour point (D) None of these

Last Answer : (A) Viscosity index

Oils and fats are obtained from (a) Animal sources (b) Vegetable sources (c) Synthesis (d) Both animal and vegetable sources

Description : Oils and fats are obtained from (a) Animal sources (b) Vegetable sources (c) Synthesis (d) Both animal and vegetable sources

Last Answer : Ans:(d)

Glycerine and what other substance are made by heatin animal fats or vegetable oils with sodium hydroxide?

Description : Glycerine and what other substance are made by heatin animal fats or vegetable oils with sodium hydroxide?

Last Answer : ANSWER: SOAP

Neoprene which is used for making shoe heels & belts is superior to natural rubber in its stability to aerial oxidation and resistance to oils & other solvents. The monomer used for making neoprene is (A) Chloroethane (B) Chloroprene (C) Isoprene (D) None of these

Description : Neoprene which is used for making shoe heels & belts is superior to natural rubber in its stability to aerial oxidation and resistance to oils & other solvents. The monomer used for making neoprene is (A) Chloroethane (B) Chloroprene (C) Isoprene (D) None of these

Last Answer : (B) Chloroprene

Aniline point is the (A) Characteristic property of diesel & lubricating oils (B) Measure of aromatic content of oil (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : Aniline point is the (A) Characteristic property of diesel & lubricating oils (B) Measure of aromatic content of oil (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B

Coal tar fuels (CTF) as compared to petroleum based fuel oils have higher (A) Calorific value (B) Higher C/H ratio (C) Sulphur content (D) Difference in gross & net calorific value

Description : Coal tar fuels (CTF) as compared to petroleum based fuel oils have higher (A) Calorific value (B) Higher C/H ratio (C) Sulphur content (D) Difference in gross & net calorific value

Last Answer : (B) Higher C/H ratio

Unsaturated oils compared to saturated oils have (A) Lower melting point & higher reactivity to oxygen (B) Higher melting point & higher reactivity to oxygen (C) Lower melting point & lower reactivity to oxygen (D) Higher melting point & lower reactivity to oxygen

Description : Unsaturated oils compared to saturated oils have (A) Lower melting point & higher reactivity to oxygen (B) Higher melting point & higher reactivity to oxygen (C) Lower melting point & lower reactivity to oxygen (D) Higher melting point & lower reactivity to oxygen

Last Answer : (A) Lower melting point & higher reactivity to oxygen

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

Graphite is used in nuclear reactor as (A) Insulation lining of the reactor (B) Fuel (C) Lubricant (D) Retarder of neutron velocity

Description : Graphite is used in nuclear reactor as (A) Insulation lining of the reactor (B) Fuel (C) Lubricant (D) Retarder of neutron velocity

Last Answer : (D) Retarder of neutron velocity

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

__________ is the most suitable lubricant for drawing mild steel wires? (A) Kerosene (B) Water (C) Sodium stearate (D) Lime water

Description : __________ is the most suitable lubricant for drawing mild steel wires? (A) Kerosene (B) Water (C) Sodium stearate (D) Lime water

Last Answer : (C) Sodium stearate

Higher efficiency in the combustion of solid fuel cannot be achieved by (A) Proper fuel preparation (B) Keeping the flue gas exhaust temperature very high (C) Adopting efficient-fuel firing technique & equipment (D) Supplying correct quantity of combustion air

Description : Higher efficiency in the combustion of solid fuel cannot be achieved by (A) Proper fuel preparation (B) Keeping the flue gas exhaust temperature very high (C) Adopting efficient-fuel firing technique & equipment (D) Supplying correct quantity of combustion air

Last Answer : (B) Keeping the flue gas exhaust temperature very high

Vegetable oils contain large quantity of glycerides of unsaturated acids. When the vegetable oils contain high amount of saturated fatty acids, it is termed as __________ oil. (A) Drying (B) Semi-drying (C) Non-drying (D) None of these

Description : Vegetable oils contain large quantity of glycerides of unsaturated acids. When the vegetable oils contain high amount of saturated fatty acids, it is termed as __________ oil. (A) Drying (B) Semi-drying (C) Non-drying (D) None of these

Last Answer : (C) Non-drying

Bitumen in (A) Solid state, is called asphalt (B) Semi fluid state, is called mineral tar (C) Fluid state, is called petroleum (D) All the above

Description : Bitumen in (A) Solid state, is called asphalt (B) Semi fluid state, is called mineral tar (C) Fluid state, is called petroleum (D) All the above

Last Answer : Answer: Option D

Biosphere describes the earth realm where life occurs What describes the entire solid earth realm and is composed of mineral matter?

Description : Biosphere describes the earth realm where life occurs What describes the entire solid earth realm and is composed of mineral matter?

Last Answer : ANSWER: LITHOSPHERE

The liquid used for the washing of coal in an industrial coal washery is a mixture of water and (A) Carbon tetrachloride (B) Sand (40%) (C) Mineral oil of high viscosity & specific gravity (1.6) (D) None of these

Description : The liquid used for the washing of coal in an industrial coal washery is a mixture of water and (A) Carbon tetrachloride (B) Sand (40%) (C) Mineral oil of high viscosity & specific gravity (1.6) (D) None of these

Last Answer : (B) Sand (40%)

Use of chlorine in the treatment of sewage (A) Helps in grease separation (B) Increases the biological oxygen demand (BOD) (C) Causes bulking of activated sludge (D) Aids in flocculation

Description : Use of chlorine in the treatment of sewage (A) Helps in grease separation (B) Increases the biological oxygen demand (BOD) (C) Causes bulking of activated sludge (D) Aids in flocculation

Last Answer : (A) Helps in grease separation

Consider the following statements: 1. Mercury metal exists as a liquid at room temperature. 2. The property of metals by which they can be beaten into thin sheets is called malleability 3. Neutral fats such as butter and vegetable oils are mostly triglycerides. 4. The size of an atom is of the order of 10 - 15 m. The correct statements are: (a) 1, 2 and 4 only (b) 1, 3 and 4 only (c) 2, 3 and 4 only (d) 1, 2 and 3 only

Description : Consider the following statements: 1. Mercury metal exists as a liquid at room temperature. 2. The property of metals by which they can be beaten into thin sheets is called malleability 3. Neutral fats such as butter and vegetable oils ... b) 1, 3 and 4 only (c) 2, 3 and 4 only (d) 1, 2 and 3 only

Last Answer : Ans:(d)

Which of the following statements is not true about triacylglycerols? (a) When solids and semisolids at room temperature, they are called fats. (b) When liquids at room temperature, they are called oils. (c) When hydrolyzed, they produce glycerol and carboxylate salts. (d) Triacylglycerols with low melting points are composed of saturated fatty acids, causing them to be liquids at room temperature

Description : Which of the following statements is not true about triacylglycerols? (a) When solids and semisolids at room temperature, they are called fats. (b) When liquids at room temperature, they are ... low melting points are composed of saturated fatty acids, causing them to be liquids at room temperature

Last Answer : Triacylglycerols with low melting points are composed of saturated fatty acids, causing them to be liquids at room temperature

Tin based white metals are used, where bearings are subjected to (A) High pressure & load (B) Low pressure & load (C) High temperature (D) Large surface wear

Description : Tin based white metals are used, where bearings are subjected to (A) High pressure & load (B) Low pressure & load (C) High temperature (D) Large surface wear

Last Answer : (A) High pressure & load

[SFW] What's your favorite lubricant, and why?

Description : [SFW] What's your favorite lubricant, and why?

Last Answer : answer:Full synthetic oil for my Integra's (DC1) motor: Far less prone to breakdown and contamination than dino juice. Every molecule of synthetic oil has lubricating properties, not so with natural ... longer periods between changes, a necessity as my car is currently in storage in damp Florida.

Is there a food safe lubricant?

Description : Is there a food safe lubricant?

Last Answer : Vegetable oil? Butter? Lard? They will get rancid, of course, in a very short time.