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 : Solid shaft is costlier than hollow shaft of same weight. a) True b) False
Last Answer : b) False
Description : The strength of hollow shaft is more than the strength of solid shaft of same weight. a) True b) False
Last Answer : a) True
Description : The stiffness of solid shaft is more than the stiffness of hollow shaft with same weight. a) True b) False
Description : If shaft diameter is 60mm, how many bolts are recommended for rigid flange coupling? a) 2 b) 3 c) 4 d) 5
Last Answer : c) 4
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 : 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 : If shaft diameter is 40mm, calculate the diameter of sleeves in clamp coupling. a) 100mm b) 80mm c) 60mm d) 40mm
Last Answer : a) 100mm
Description : Does shaft has to be shifted i axial direction to remove clamp coupling. a) Yes b) No
Last Answer : b) No
Description : While designing a flange coupling, care is taken so that (A) Shaft is the weakest component (B) Bolts are the weakest component (C) Key is the weakest component (D) The flange is the weakest component
Last Answer : (C) Key is the weakest component
Description : In designing a flange coupling, the pitch circle diameter of bolts is taken as (where d = Diameter of the shaft) (A) 2 d (B) 3 d (C) 4 d (D) 5 d
Last Answer : (B) 3 d
Description : Antifriction bearings are (a) thick lubricated bearings (b) plastic bearings (c) ball and roller bearings (d) thin lubricated bearings
Last Answer : (c) ball and roller bearings
Description : Which bearing is Antifriction bearing A. Thick lubrication bearing B. Thin lubrication bearing C. Rolling or ball bearing D. None
Last Answer : C. Rolling or ball bearing
Description : Rolling contact bearing is also called as A. Plastic bearing B. Thin lubrication bearing C. Thick lubrication bearing D. Antifriction bearing.
Last Answer : D. Antifriction bearing.
Description : The rolling contact bearings are known as (a) thick lubricated bearings (b) plastic bearings (c) thin lubricated bearings (d) antifriction bearings
Last Answer : (d) antifriction bearings
Description : Boundary lubricated bearing is (A) Thick film bearing (B) Thin film bearing (C) Hydrodynamic bearing (D) Hydrostatic bearing
Last Answer : (B) Thin film bearing
Description : Write About Muff Coupling?
Last Answer : It is a hollow piece which is used with key to connect the shafts. It may be found in cylindrical muff,half lap muff or split muff type. A gib head key or a saddle key is inserted between the coupling and shafts through out for connecting the shafts.
Description : A transmission shaft subjected to pure bending moment should be designed on the basis of (A) Maximum principal stress theory (B) Maximum shear stress theory (C) Distortion energy theory (D) Goodman or Soderberg diagrams
Last Answer : (A) Maximum principal stress theory
Description : The hub is treated as a solid shaft while calculating torsional shear stress in the hub. a) True b) False
Description : The bending moment ‘M’ and a torque ‘T’ is applied on a solid circular shaft. If the maximum bending stress equals to maximum shear stress developed, then ‘M’ is equal to (A) T/2 (B) T (C) 2 T (D) 4 T
Last Answer : (A) T/2
Description : A hollow shaft of 1 m length is designed to transmit a power of 30 kW at 700 rpm. The maximum permissible angle of twist in the shaft is 1o. The inner diameter of the shaft is 0.7 times the outer diameter. The modulus of ... shaft is _______. (a) 43 to 45 (b) 50to 60 (c) 70 to 80 (d) 85 to 100
Last Answer : (a) 43 to 45
Description : Actual stress in the bolts of a flanged coupling of a shaft will be (a) More than the designed strength (b) Less than the designed strength (c) Neither more nor less than the designed strength (d) None
Last Answer : (b) Less than the designed strength
Description : Arithmetic mean area can be used in heat transfer problem to calculate the heat flow by conduction through a cylinder which is (A) Thin walled having the value of Ao Ai /< 2 (B) Thick walled (C) Having the value of Ao /Ai > 2 (D) Both (B) and (C)
Last Answer : (A) Thin walled having the value of Ao Ai /< 2
Description : Cylinder having inner diameter to wall thickness ratio less than 15 are a) Thin cylinders b) Thick Cylinders c) Moderate cylinders d) none of the above
Last Answer : b) Thick Cylinders
Description : If n is the ratio of internal and external diameters of a hollow shaft, the ratio of the weight of the hollow shaft and that of solid shaft of same strength, will be (A) (1 - n²)/(1 - n²)1/2 (B) (1 - n²)/(1 - n 4 ... (1 + n 4 )1/2 (D) (1 + n 1 )/(1 + n 4 )2/3
Last Answer : (B) (1 - n²)/(1 - n 4 )2/3
Description : The ratio of the moments of resistance of a solid circular shaft of diameter D and a hollow shaft (external diameter D and internal diameter d), is (A) D 4 /(D 4 - d 4 ) (B) D 3 /(D 3 - d 3 ) (C) (D 4 - d 4 )/D 4 (D) (D 3 - d 3 )/D 3
Last Answer : (A) D 4 /(D 4 - d 4 )
Description : Solid shaft is ----------than hollow shaft of same weight. a) cheaper b) costlier c) not costlier d) not cheaper
Last Answer : b) costlier
Description : The strength of hollow shaft is more than the strength of solid shaft of ---------weight. a) same b) different c) equal d) not equa
Last Answer : a) same
Description : The stiffness of solid shaft is---------- than the stiffness of hollow shaft with same weight. a) less b) more c) equal d) not equal
Last Answer : b) more
Description : The strain energy will be higher in which shaft under the same torque (a) Solid shaft (b) Hollow shaft (c) Same in Solid as well as hollow shaft (d) None
Last Answer : (b) Hollow shaft
Description : From strength point of view, whether hollow or solid shaft will be preferable (a) Solid shaft (b) Hollow shaft (c) Both solid as well as hollow shaft (d) None
Last Answer : b) Hollow shaft
Description : For a solid or a hollow shaft subject to a twisting moment T, the torsional shearing stress t at a distance r from the centre will be (a) t = Tr/J (b) t = Tr (c) t = TJ/r (d) none of these
Last Answer : (a) t = Tr/J
Description : For the same material, length and given torque, a hollow shaft weighs……………… a solid shaft. (a) Less than (b) More than (c) Equal to (d) None of these
Last Answer : (a) Less than
Description : The strength of a hollow shaft is ……… for the same length, material and weight of a solid shaft. (a) More (b) Less (c) Equal (d) None of these
Last Answer : (b) Less
Description : For same length, same material, same length a. Weight of solid shaft is less than weight of hollow shaft b. Weight of solid shaft is more than weight of hollow shaft c. Weight of hollow and solid shafts will be same d. Sometime more sometime less
Last Answer : b. Weight of solid shaft is more than weight of hollow shaft
Description : For same weight, same material, same length a. Solid shaft is always stronger than a hollow shaft b. Solid shaft is always weaker than a hollow shaft and strength ratio will depend upon Do/Di of ... of a solid shaft is always weaker and the strength ratio will depend upon Do/Di of hollow shaft
Last Answer : b. Solid shaft is always weaker than a hollow shaft and strength ratio will depend upon Do/Di of hollow shaft
Description : Which of the following is incorrect? a. In a solid shaft maximum shear stress occurs at radius = radius of shaft b. In a solid shaft maximum shear stress occurs at center c. In a hollow ... maximum shear stress occurs at outer radius d. In a hollow shaft minimum shear stress occurs at inner radius
Last Answer : b. In a solid shaft maximum shear stress occurs at center
Description : The strength of a hollow shaft for the same length, material and weight is ---------- a solid shaft. a. less than. b. more than. c. equal to. d. not equal to.
Last Answer : b. more than.
Description : The ratio of strength of a hollow shaft to that of a solid shaft subjected to torsion if both are of the same material and of the same outer diameters, the inner diameter of hollow shaft being half of the outer diameter is a. 15/16 b. 16/15 c. 7/8 d. 8/7
Last Answer : a. 15/16