Description : The coefficient of fluctuation of speed, when the maximum and minimum speeds are 300rpm and 290 rpm (A) 0.034 (B) 0.017 (C) 0.008 (D) 0/004
Last Answer : (A) 0.034
Description : The coefficient of fluctuation of speed of flywheel is 1. ratio of maximum and minimum speeds during the cycle 2. ratio of maximum fluctuation of speed to the mean speed 3. ratio of mean ... maximum fluctuation of speed during the cycle 4. sum of maximum fluctuation of speed and the mean speed
Last Answer : 2. ratio of maximum fluctuation of speed to the mean speed
Description : The difference the maximum and minimum speeds during a cycle is called (A) Fluctuation of speed (B) Maximum fluctuation of speed (C) Coefficient of fluctuation of speed (D) None of the above
Last Answer : (B) Maximum fluctuation of speed
Description : The coefficient of fluctuation of speed of flywheel is, (A) Ratio of maximum and minimum speeds during the cycle (B) Ratio of maximum fluctuation of speed to the mean speed (C) Ratio of ... maximum fluctuation of speed during the cycle (D) Sum of maximum fluctuation of speed and the mean speed
Last Answer : (B) Ratio of maximum fluctuation of speed to the mean speed
Description : The coefficient of fluctuation of energy of flywheel is 1. ratio of maximum fluctuation of energy to work done per cycle 2. ratio of to work done per cycle to maximum fluctuation of energy ... minimum kinetic energy during the cycle 4. ratio of maximum and minimum kinetic energy during the cycle
Last Answer : 1. ratio of maximum fluctuation of energy to work done per cycle
Description : The coefficient of fluctuation of energy of flywheel is, (A) Ratio of maximum fluctuation of energy to work done per cycle (B) Ratio of to work done per cycle to maximum fluctuation of ... minimum kinetic energy during the cycle (D) Ratio of maximum and minimum kinetic energy during the cycle
Last Answer : (A) Ratio of maximum fluctuation of energy to work done per cycle
Description : Reciprocal of coefficient of fluctuation of speed is called 1. fluctuation of energy 2. fluctuation of speed 3. maximum fluctuation of speed 4. coefficient of fluctuation of speed
Last Answer : 4. coefficient of fluctuation of speed
Description : The coefficient of fluctuation of energy = (A) Maximum fluctuation of energy / work done per cycle (B) Fluctuation of energy / Work done per cycle (C) Maximum fluctuation of energy / Mean speed (D) Fluctuation of energy / Mean speed
Last Answer : (A) Maximum fluctuation of energy / work done per cycle
Description : Reciprocal of Coefficient of fluctuation of speed is called (A) Fluctuation of speed (B) Coefficient of steadiness (C) Maximum fluctuation of speed (D) None of the above
Last Answer : (B) Coefficient of steadiness
Description : The ratio of maximum fluctuation of speed to the mean speed is called (A) Fluctuation of speed (B) Maximum fluctuation of speed (C) Coefficient of fluctuation of speed (D) None of the above
Last Answer : (C) Coefficient of fluctuation of speed
Description : The maximum fluctuation of speed of flywheel is, (A) Difference between maximum and minimum speeds during the cycle (B) Difference between maximum and mean speeds during the cycle (C) Difference ... and minimum speeds during the cycle (D) Mean of maximum and minimum speeds during the cycle
Last Answer : (A) Difference between maximum and minimum speeds during the cycle
Description : The coefficient of fluctuation of speed of Flywheel is given by 1. (N1-N2)/N 2. (N1+N2)/N 3. (N1-N2) x N
Last Answer : 1. (N1-N2)/N
Description : The coefficient of fluctuation of speed of flywheel is given by, (A) (ωmax - ωmin)/ω (B) 2 (ωmax - ωmin)/ (ωmax + ωmin) (C) 2 (nmax - nmin)/ (nmax + nmin) (D) Any one of the above
Last Answer : (D) Any one of the above
Description : The maximum fluctuation of energy of flywheel is 1. difference between maximum and minimum kinetic energy during the cycle 2. difference between maximum and mean kinetic energy during the cycle 3. ... kinetic energy during the cycle 4. mean of maximum and minimum kinetic energy during the cycle
Last Answer : 1. difference between maximum and minimum kinetic energy during the cycle
Description : The maximum fluctuation of energy of flywheel is, (A) Difference between maximum and minimum kinetic energy during the cycle (B) Difference between maximum and mean kinetic energy during the cycle ... kinetic energy during the cycle (D) Mean of maximum and minimum kinetic energy during the cycle
Last Answer : (A) Difference between maximum and minimum kinetic energy during the cycle
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.
Description : A flywheel of moment of inertia 9.8kgm 2 fluctuates by 30 rpm for a fluctuation in energy of 1936 joules. The means speed of flywheel is (in rpm) 1. 600 2. 900 3. 968 4. 2940
Last Answer : 1. 600
Description : A flywheel connected to a punching machine has to supply energy of 400 Nm while running at a mean angular speed of 20 rad/s. If the total fluctuation of speed is not exceed to in kgm 2 is 1. 25 2. 50 3. 100 4. 125
Last Answer : 1. 25
Description : A flywheel is used 1. to limit the fluctuation of speed during each cycle 2. to control the mean speed of the engine 3. to maintain a constant speed 4. to come into action when the speed varies
Last Answer : 1. to limit the fluctuation of speed during each cycle
Description : Maximum fluctuation of energy = 1. Max KE – Min KE 2. Max KE + Min KE 3. Max KE > Min KE 4. Max KE < Min KE
Last Answer : 1. Max KE – Min KE
Description : Maximum fluctuation of energy = (A) Max. KE – Min. KE (B) Max. KE + Min. KE (C) (Max. KE – Min. KE)/2 (D) (Max. KE + Min. KE)/2
Last Answer : (A) Max. KE – Min. KE
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 : A ball is dropped from a height of 2.25 m on a smooth floor and it rises to a height of 1 m after the first bounce. The coefficient of restitutions between the ball and the floor is a.107 dynes b.0.33 c.0.44 d.0.57 e.0.67
Last Answer : e. 0.67
Description : If the coefficient of friction on the road surface is 0.15 and a maximum super-elevation 1 in 15 is provided, the maximum speed of the vehicles on a curve of 100 metre radius, is (A) 32.44 km/hour (B) 42.44 kg/hour (C) 52.44 km/hour (D) 62.44 km/hour
Last Answer : Answer: Option C
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 : 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
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
Description : Define coefficient of fluctuation of energy.
Last Answer : Definition of Coefficient of Fluctuation of Energy: It may be defined as the ratio of the maximum fluctuation of energy to the work done per cycle. Mathematically it is expressed as;
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 : 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
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 : Calculate fatigue stress concentration factor, when theoretical stress concentration factor is 1.62 and notch sensitivity is equal to 0.9 a. 1.558 b. 3.358 c. 1.162 d. None of the above
Last Answer : a. 1.558
Description : The listed life of a rolling bearing, in a catalog is the, (a) minimum expected life (b) maximum expected life (c) average life (d) none of the mentioned
Last Answer : (a) minimum expected life
Description : The stress which vary from a minimum value to a maximum value of the same nature (i.e. tensile or compressive) is called (a) repeated stress (b) yield stress (c) fluctuating stress (d) alternating stress
Last Answer : (c) fluctuating stress
Description : The shaft is always stepped with ________ diameter at the middle portion and __________ diameter at the shaft ends. a) Minimum, maximum b) Maximum, minimum c) Minimum, minimum d) Zero, infinity
Last Answer : b) Maximum, minimum
Description : Principal planes are those planes on which a. Normal stress is maximum b. Normal stress is minimum c. Normal stress is either maximum or minimum d. Shear stress is maximum
Last Answer : c. Normal stress is either maximum or minimum
Description : Principal stresses are a. Firstly Maximum and minimum shear stresses b. Secondly Maximum and minimum normal stresses c. Both (a) & (b) d. None
Last Answer : b. Secondly Maximum and minimum normal stresses
Description : Assertion (A): Oil as a cutting fluid result in a lower coefficient of friction. Reason (R): Oil forms a thin liquid film between the tool face and chip, and it provides 'hydrodynamic lubrication'. [IES- 2000] (a ... explanation of A (c) A is true but R is false (d) A is false but R is true
Last Answer : (c) A is true but R is false
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 : Which of the following are not true for petroff’s equation? a) Shaft is considered concentric with the bearing b) Bearing is subjected to light load c) Is used to find coefficient of friction d) Frictional torque is given by fpr2l
Last Answer : d) Frictional torque is given by fpr2l
Description : In trapezoidal threads, f (coefficient of friction) can be taken as a) f sec θ b) f cos θ c) f sin θ d) f cosec θ
Last Answer : a) f sec θ
Description : Efficiency of the screw _______ with increase of coefficient of friction. a) decreases b) increases c) has no effect d) cannot be determined
Last Answer : a) decreases
Description : Self-locking takes place when a) Coefficient of friction is equal to or greater than the tangent of the helix angle b) Coefficient of friction is lesser than or equal to the tangent of the helix ... friction is equal to or greater than the tangent of the helix angle d) None of the mentioned
Last Answer : c) Coefficient of friction is equal to or greater than the tangent of the helix angle
Description : cylindrical rod subjected to a tensile strain within the elastic limit undergoes a volume change. If the volume strain is equal to half the tensile strain, then the Poisson's ratio of the rod is (A) 0 (B) 0.33 (C) 0.44 (D) 0.25
Last Answer : Option C
Description : Different types of bearings are designed to operate at different operating speeds. Speed is specified as the maximum (a) rpm (b) metres/second (c) metres/minute (d) metres/hour
Last Answer : (b) metres/second
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 : 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 : Calculate the moment of inertia about the axis parallel to welds and shift it to CG by considering thickness of welds t. a) tɜ+2000t b) None of the listed c) 250000 t d) 125000 t
Last Answer : c) 250000 t