Description : We often sprinkle talcum powder on the carom board . This is done to reduce ______ between the board and the striker. a) friction b)movement c)speed d)contact
Last Answer : a) friction
Description : The skidding of vehicle on snow is because of very little _______. a) pull b)friction c)push d)none
Last Answer : b)friction
Description : A ball bearing is used in shafts of motors, dynamos to reduce ______. a) movement b)friction c)speed d)none
Description : Limiting force of friction is the?
Last Answer : Limiting force of friction is the friction force acting when the body is just about to move.
Description : On the ladder resting on the ground and leaning against a smooth vertical wall, the force of friction will be?
Last Answer : On the ladder resting on the ground and leaning against a smooth vertical wall, the force of friction will be zero at its upper end.
Description : On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be?
Last Answer : On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be upwards at its upper end.
Description : Write two advantages and two disadvantages of friction.
Last Answer : They change the direction of the objects They change the size of the objects
Description : What is Friction?
Last Answer : Friction is the force that opposes the relative motion or tendency to such motion of two bodies in contact. If we try to push a block of wood across a table, there are two opposing forces ... table) the object moves further and further before stopping. This demonstrates Galileo's law of inertia too.
Description : Describe with neat diagram air friction damping.
Last Answer : Air Friction Damping: Here air trapped in the chamber works as damping medium for the piston movement connected to the spindle. The piston moves in the air chamber. The clearance between piston and ... will be the damping torque, bringing the pointer to the equilibrium position quickly.
Description : The friction losses in Real Transformers are : (A) 0% (B) 5% (C) 25% (D) 50%
Last Answer : A
Description : Kinetic friction is the?
Last Answer : Kinetic friction is the friction force acting when the body is in motion.
Description : Tangent of angle of friction is equal to?
Last Answer : Tangent of angle of friction is equal to coefficient of friction.
Description : Dynamic friction as compared to static friction is?
Last Answer : Dynamic friction is less compared to static friction.
Description : Coulomb friction is the friction between?
Last Answer : Coulomb friction is the friction between bodies having relative motion.
Description : Coefficient of friction is the?
Last Answer : Coefficient of friction is the ratio of limiting friction and normal reaction.
Description : The ratio of limiting friction and normal reaction is known as?
Last Answer : The ratio of limiting friction and normal reaction is known as coefficient of friction.
Description : The coefficient of friction depends on?
Last Answer : The coefficient of friction depends on nature of surface.
Description : Angle of friction is the?
Last Answer : Angle of friction is the angle between normal reaction and the resultant of normal reaction and the limiting friction.
Last Answer : The normal value of adhesion friction is 0.25.
Last Answer : The friction at the track is proportional to speed.
Description : Air resistance ______ with an increase in the speed of the object moving through it. a) increases b)decreases c)remains same d)no change
Last Answer : a) increases
Description : Liquid pressure at any point inside the liquid, depends upon _______of the liquid and the height of liquid column above that point. a) area b)density c)weight d)none
Last Answer : b)density
Description : A sliding contact bearing is operating under stable condition. The pressure developed in oil film is p when the journal rotates at N rpm. The dynamic viscosity of lubricant is μ and effective coefficient of ... to p and f) (d) f is directly proportional to μ and inversely proportional to N
Last Answer : (b) f is directly proportional to μ and N
Description : The ball bearings are provided with a cage (a) to reduce friction (b) to facilitate slipping of balls (c) to prevent the lubricant from flowing out (d) to maintain the balls at a fixed distance apart
Last Answer : (d) to maintain the balls at a fixed distance apart
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
Description : Which one of the following is not the law of dry friction? a.If friction is neglected, the reactions are always normal to the surfaces on contact b.Friction always acts to oppose the relative motion of ... its maximum value d.The force of friction is always normal to the surface e.All of the above
Last Answer : d. The force of friction is always normal to the surface
Description : Pick up wrong statement about friction force for dry surfaces. Friction force is (A) Proportional to normal load between the surfaces (B) Dependent on the materials of contact surface (C) Proportional to velocity of sliding (D) Independent of the area of contact surfaces
Last Answer : (C) Proportional to velocity of sliding
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
Description : Assertion (A): In anti-friction bearings, the frictional resistance is very low as the shaft held by it remains in floating condition by the hydrodynamic pressure developed by the lubricant. [IES-2006] Reason (R): In hydrodynamic ... of A (c) A is true but R is false (d) A is false but R is true
Last Answer : (d) A is false but R is true
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
Description : What is the substance such as oil or grease that is used to reduce friction.?
Last Answer : What is the answer ?
Description : In cold countries ethylene glycol is added to water in car radiators. This helps to (a) Reduce the viscosity (b) Make water a better lubricant (c) Lower the freezing point (d) Lower the boiling poin
Last Answer : Lower the freezing point
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
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
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
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
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
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
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
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
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
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
Description : Incorrect statement for co-efficient of friction could be that A. The coefficient of friction is denoted by the Greek letter µ. B. The coefficient of friction is directly proportional to ... D. The coefficient of friction is inversely proportional to the force pressing the surfaces together
Last Answer : The coefficient of friction is constant even in the conditions of fast slipping and high contact pressure
Description : Kinetic friction is always A. lesser than static friction B. greater than static friction C. equal to static friction D. equal to contact force
Last Answer : lesser than static friction
Description : It is easier to roll a barrel than to pull it because (a) the full weight of the barrel comes into play when it is pulled (b) rolling friction is much less than sliding friction (c) the surface ... in contact with the road is more in the case of pulling (d) of a reason other than those mentioned
Last Answer : Ans:(b)
Description : The coefficient of friction depends on (A) Area of contact (B) Shape of surfaces (C) Strength of surfaces (D) Nature of surface
Last Answer : (D) Nature of surface
Description : When the steel bars are embedded in concrete. The concrete after setting, adheres to the surface of the bars and thus resist any force that tends to pull or push this road. The intensity of this adhesive force is called. (a) Bond stress (b) Shear stress (c) Compressive stress (d) All of these
Last Answer : (a) Bond stress
Description : In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than (A) Frictional force (B) Viscosity (C) Surface friction (D) All of the above
Last Answer : Answer: Option D
Description : Can someone explain to me what's the thing with surface normal and friction force?
Last Answer : Force normal is the force facing upwards, perpendicular to the object. It is what prevents you from falling down when sitting on a chair. Frictional force can be in any direction depending on context. Imagine a ... are having trouble with? At this point, your Q what's the thing is rather vague.
Description : A uniform cylinder of weight W is rolling while slipping on a rough horizontal surface under the influence of a horizontal force. The force of friction between the cylinder and the surface is a. ... c.Indeterminate d.Determinate but depends on the acceleration of the cylinder e.None of the above
Last Answer : c. Indeterminate