Description : The length to diameter ratio for a square bearing is (A) More than 1 (B) Less than 1 (C) 8 (D) 1
Last Answer : (D) 1
Description : Needles bearing consist of rollers of small diameter and very small length. (a) True (b) False
Last Answer : (b) False
Description : Needles bearing consist of rollers of small diameter and very small length. a) True b) False
Last Answer : b) False
Description : A rolling contact bearing is specified as X307. Calculate the bearing diameter. (a) 35 mm (b) 28 mm (c) 21 mm (d) 7 mm
Last Answer : (a) 35 mm
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 : 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
Last Answer : (a) S = (μN s /p) (r/c) 2
Description : If number of coils are 8 and wire diameter of spring 3mm, then solid length is given by? a) None of the listed b) 27mm c) 24mm d) 21mm
Last Answer : c) 24mm
Description : In case of partial bearing, the angle of contact of the bushing with the journal is (A) 270° (B) More than 180° (C) Less than 180° (D) 360°
Last Answer : (C) Less than 180°
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.
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
Description : The inner diameter of washer is (A) Equal to the nut size (B) More than the nut size (C) Less than the nut size (D) Independent of the nut size
Last Answer : (B) More than the nut size
Description : When two concentric springs are made of same material, having same free length and compressed equally by axial load, then the load shared by each spring is proportional to (A) Spring index of each spring ... spring (C) Mean coil diameter of each spring (D) Square of wire diameter of each spring
Last Answer : (D) Square of wire diameter of each spring
Description : The shock absorbing capacity of bolts can be increased by a) Increasing the shank diameter b) Decreasing the length of shank portion of bolt c) Increase the shank diameter and decreasing the length of shank d) None of the listed
Last Answer : d) None of the listed
Description : If shaft diameter is 40mm, calculate the length of sleeves in clamp coupling. a) 80mm b) 140mm c) 100mm d) 120mm
Last Answer : b) 140mm
Description : A muff coupling is connecting two shafts. The torque involved is 650N-m. The shaft diameter is 45mm with length and height of the key being 14mm and 80mm respectively. Find the compressive stress induced in the key. a) 70.1 N/mm2 b) 51.6N/mm2 c) 45.5N/mm2 d) None of the listed
Last Answer : b) 51.6N/mm2
Description : A muff coupling is connecting two shafts. The torque involved is 650N-m. The shaft diameter is 45mm with length and breadth of the key being 14mm and 80mm respectively. Find the shear stress induced in the key. a) 30.2N/mm2 b) 25.8N/mm2 c) 34.4N/mm2 d) None of the listed
Last Answer : b) 25.8N/mm2
Description : Determine the length of kennedy key required to transmit 1200N-m and allowable shear in the key is 40N/mm2. The diameter of shaft and width of key can be taken as 40mm and 10mm respectively. a) 49mm b) 36mm c) 46mm d) 53mm
Last Answer : d) 53mm
Description : Calculate the shaft diameter on rigidity basis if torsional moment is 196000N-mm, length of shaft is 1000mm. Permissible angle of twist per meter is 0.5’ and take G=79300N/mm2. a) None of the listed b) 41.2mm c) 35.8mm d) 38.8mm
Last Answer : b) 41.2mm
Description : The shafts will have same strength on the basis of torsional rigidity, if (A) Diameter and length of both shafts is same (B) Material of both shafts is same (C) Angle of twist for both shafts is same (D) All of above conditions are satisfied
Last Answer : (D) All of above conditions are satisfied
Description : The standard length for square or flat key in terms of shaft diameter (D) is, (A) d (B) 2d (C) 1.5d (D) 2.5d
Last Answer : (C) 1.5d
Description : The spring index is, (A) Ratio of wire diameter to mean coil diameter (B) Force per unit cross-sectional area of spring (C) Ratio of mean coil diameter to wire diameter (D) Force required to produce unit deflection
Last Answer : (C) Ratio of mean coil diameter to wire diameter
Description : The stiffness of spring is, (A) Deflection per unit of axial force (B) Force per unit cross-sectional area of spring (C) Ratio of mean coil diameter to wire diameter (D) Force required to produce unit deflection
Last Answer : (D) Force required to produce unit deflection
Description : The spring index is the ratio of wire diameter to mean coil diameter. a) True b) False
Last Answer : a) True
Description : A cylinder roller creates lesser noise than a deep groove ball bearing. (a) True (b) False
Description : Temperature rise in partial bearing is ____ than full bearing. a) Lesser b) Greater c) Equal
Last Answer : a) Lesser
Description : Cylinder roller creates lesser noise than deep groove ball bearing. a) True b) False
Description : The diameter of knuckle pin in the knuckle joint is usually... A. 0.5 d B. 0.8 d C. 1.5 d D. d
Last Answer : D. d
Description : If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the diameter of each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. Permissible tensile stress is 80N/mm2. a) 27mm b) 25mm c) 23mm d) 21mm
Last Answer : a) 27mm
Description : If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the tensile force on each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. a) 51234.4N b) 45968.3N c) 41666.7N d) None of the listed
Last Answer : c) 41666.7N
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
Description : Partial bearing is preferred over journal bearing. a) True b) No c) More friction losses d) Can’t be determined
Description : The distribution of the forces along the length of key fitted in a shaft (A) Varies linearly (B) Is uniform throughout (C) Varies exponentially, being more near the torque-input end (D) Varies exponentially, being less near the torque-input end
Last Answer : (C) Varies exponentially, being more near the torque-input end
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 : The purpose of lubrication in an antifriction bearing is (a) to reduce the friction between balls and races (b) dissipation of frictional heat prevention of corrosion (c) protection of the bearing from dirt and other foreign particles (d) all of the mentioned
Last Answer : (d) all of the mentioned
Description : _____ is a surface fatigue failure which occurs when the load on the bearing part exceeds the surface endurance strength of the material. (a) Scoring (b) Pitting (c) Corrosion
Last Answer : (b) Pitting
Description : Extreme Pressure (EP) additives cause ______ wear in the bearing parts. (a) abrasive (b) corrosive (c) pitting (d) fatigue
Last Answer : (b) corrosive
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
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
Description : The dynamic load-carrying capacity of a bearing is defined as the radial load in radial bearings that can be carried for a minimum life of 1000 revolutions. (a) True (b) False
Description : The rated life of a bearing varies (a) directly as load (b) inversely as the square of the load (c) inversely as the cube of the load
Last Answer : (c) inversely as the cube of the load
Description : The life of an individual ball bearing is the time period for which it works without any signs of failures. (a) True (b) False
Description : Stribeck equation gives the dynamic load capacity of the bearing. (a) True (b) False
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
Description : An antifriction bearing consists of (a) rolling elements (b) races (c) cages (d) all of the listed
Last Answer : (d) all of the listed
Description : Which one of the following parts of a ball bearing acts as a barrier between the balls preventing them from bumping into each other? (a) Inner race (b) Outer race (c) Rolling element (d) Cage
Last Answer : (d) Cage