Recent questions tagged dynamics-of-machinery

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 : Flywheel absorbs energy during those periods of crank rotation when 1. The twisting moment is greater than the resisting moment 2. The twisting moment is equal to the resisting moment 3. The twisting moment is less than resisting moment 4. The load on engine falls

Last Answer : 1. The twisting moment is greater than the resisting moment

Description : In a flywheel the safe stress is 25.2MN/m 2 and the density is 7 g/cm 3 . Then what is the maximum peripheral velocity ? 1. 30m/s 2. 45m/s 3. 60m/s 4. 120m/s

Last Answer : 3. 60m/s

Description : Calculate the coefficient of fluctuation of speed if maximum speed is 2500rpm and minimum speed is 1800rpm. 1. 1.44 2. 1.33 3. 0.33 4. 0.44

Last Answer : 3. 0.33

Description : When the driving torque is more than load torque, flywheel is ______ 1. Accelerated 2. Decelerated 3. Constant velocity 4. Can’t be determined

Last Answer : 1. Accelerated

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 radius of Gyration (k) for Rim Type Flywheel having radius ‘r’ is given by 1. k = 2r 2. k = r/2 3. k = r 4. k = r/3

Last Answer : 3. k = r

Description : Which of the following is used to control the speed variations of the engine caused by the fluctuations of the engine turning moment? 1. D-slide valve 2. Governor 3. Flywheel 4. Meyer’s expansion valve

Last Answer : 3. Flywheel

Description : A circular solid of uniform thickness 20 mm, radius 200 mm and mass 20 kg, is used as a flywheel. If it rotates at 600 rpm, the kinetic energy of the flywheel, in joules is 1. 395 2. 790 3. 1580 4. 3160

Last Answer : 2. 790

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 : Split flywheel is made to 1. avoid cooling stress 2. reduce weight 3. increase weight 4. maximize large centrifugal force

Last Answer : 1. avoid cooling stress

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 : 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 : The flywheel is accelerate when 1. driving torque > load torque 2. driving torque < load torque 3. driving torque = load torque 4. driving torque / load torque

Last Answer : 1. driving torque > load torque

Description : Energy stored in flywheel in the form of 1. heat energy 2. kinetic energy 3. solar energy 4. thermal energy

Last Answer : 2. kinetic energy

Description : In vehicle flywheel is place between 1. clutch and propeller shaft 2. engine and clutch 3. before engine 4. propeller shaft and differential

Last Answer : 2. engine and clutch

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 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 cross section of flywheel arm is 1. I section 2. Rectangular 3. Elliptical 4. Circular

Last Answer : 3. Elliptical

Description : For finding out the bending moment for the arm (spoke) of flywheel the arm is assumed as 1. a cantilever beam fixed at the rim and subjected to tangential force at the hub 2. a simply ... tangential force at the rim 4. a fixed beam fixed at hub and rim and carrying uniformly distributed load

Last Answer : 3. a cantilever hub fixed at the rim and subjected to tangential force at the rim

Description : The hub diameter of the flywheel is taken as 1. 2.5(shaft diameter) 2. 1.5(shaft diameter) 3. 4(shaft diameter) 4. 2(shaft diameter)

Last Answer : 4. 2(shaft diameter)

Description : The spokes of the flywheel are subjected to 1. direct shear stress 2. torsional shear stress 3. tensile stress 4. compressive stress

Last Answer : 3. tensile stress

Description : The rim of the flywheel is subjected to, 1. direct tensile stress and bending stress 2. torsional shear stress and bending stress 3. direct shear stress and bending stress 4. compressive stress and bending stress

Last Answer : 1. direct tensile stress and bending stress

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 : A flywheel is made of 1. cast iron 2. high strength steels 3. graphic fiber reinforced polymer 4. any one of the above materials

Last Answer : 4. any one of the above materials

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 : Which of the following is (are) true? (A) Cast iron has poor tensile strength compared to steel (B) Failure of cast iron flywheel is sudden and total (C) Machinability of cast iron flywheel is poor compared to steel flywheel (D) All of the above

Last Answer : (D) All of the above

Description : The flywheel is accelerated when (A) Driving torque > Load torque (B) Driving torque < Load torque (C) Driving torque = Load torque (D) Any of the above

Last Answer : (A) Driving torque > Load torque

Description : For two stroke engine, work done/cycle is (where T m is the mean torque) (A) πT m (B) 2πT m (C) 3πT m (D) 4πT m

Last Answer : (B) 2πT m

Description : In case of solid disk flywheel, the mass (m) of disk is given by (A) πR 2 tρ (B) (π/2)R 2 tρ (C) 3πR 2 tρ (D) (3/2)πR 2 tρ

Last Answer : (A) πR 2 tρ

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 : 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 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 : The mass moment of inertia of a solid circular disk is given by (A) mR 2 /2 (B) mR 2 /3 (C) 2mR 2 /3 (D) mR 2 /4

Last Answer : (A) mR 2 /2

Description : For four stroke engine, work done/cycle is (where T m is the mean torque) (A) πT m (B) 2πT m (C) 3πT m (D) 4πT m

Last Answer : (D) 4πT m

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 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 : When the torque required by the machine is more than the torque supplied by the motor, the flywheel is (A) Accelerated (B) Retarded (C) Rotating with constant speed (D) Any of the above

Last Answer : (B) Retarded

Description : If the load on the engine is constant, the mean speed will be constant from the cycle, then (A) The governor will not operate but flywheel will be acting (B) The flywheel will be acting but ... (C) Both flywheel and governor will be acting (D) Both flywheel and governor will not be acting

Last Answer : (A) The governor will not operate but flywheel will be acting

Description : Split flywheel is made to (A) Avoid cooling stresses (B) Minimize large centrifugal forces (C) Reduce weight (D) All of the above

Last Answer : (A) Avoid cooling stresses

Description : Flywheel are generally made from (A) Cast Iron (B) High strength steel (C) Ceramics (D) All of the above

Last Answer : (D) All of the above

Description : Flywheel is used in (A) Punch press (B) Drilling machine (C) Surface grinder (D) Milling machine

Last Answer : (A) Punch press

Description : In vehicles, flywheel is placed in between (A) Engine and clutch (B) Clutch and Propeller shaft (C) Propeller shaft and Differential (D) Before engine

Last Answer : (A) Engine and clutch

Description : Energy is stored in a flywheel in the form of (A) Heat energy (B) Solar energy (C) Kinetic energy (D) Potential energy

Last Answer : (C) Kinetic energy

Description : A flywheel is used, (A) To limit the fluctuations of speed during each cycle (B) To control the mean speed of the engine (C) To maintain a constant speed (D) To come into action when the speed varies

Last Answer : (A) To limit the fluctuations of speed during each cycle

Description : The tensile stress in the rim of the flywheel is given by, Where, ρ is mass density and v is linear velocity at the mean radius of the rim. (A) ρv2/2 (B) πρv2 (C) ρv2 (D) 2 ρv2

Last Answer : (C) ρv2

Description : The hub diameter of the flywheel is taken as, (A) 2.5 (shaft diameter) (B) 1.5 (shaft diameter) (C) 4 (shaft diameter) (D) 2 (shaft diameter)

Last Answer : (D) 2 (shaft diameter)

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 spokes of the flywheel are subjected to, (A) Direct shear stress (B) Torsional shear stress (C) Tensile stress (D) Compressive stress

Last Answer : (C) Tensile stress