Often an unbalance of forces is produced in rotary or reciprocating machinery due to the
______ *
1 point
(A) Centripetal forces
(B) Centrifugal forces
(C) Friction forces
(D) Inertia forces

1 Answer

Answer :

(D) Inertia forces

Related questions

Description : The condition to be fulfilled in the design of spring for vibration isolation of a system where excitation is due to a rotating unbalance is A) ω ωn D) ω >> ωn

Last Answer : A) ω

Description : To handle smaller quantity of fluid at higher discharge pressure, use a __________ pump. (A) Reciprocating (B) Centrifugal (C) Volute (D) Rotary vacuum

Last Answer : (A) Reciprocating

Description : Most commonly used pump for lifting water in water supply mains, is  (A) Axial flow pump  (B) Reciprocating pump  (C) Rotary type pump  (D) Centrifugal pumps 

Last Answer : (A) Axial flow pump 

Description : Differentiate between : (i) Reciprocating and rotary air compressor (ii) Centrifugal and axial flow compressor

Last Answer : (i) Reciprocating and rotary air compressor: Sr. No. Reciprocating air compressor  Rotary air compressor  1 It is having to and fro motion. It is having rotary ... I.C. engine and for refrigerants and industrial gases. Used universally with large gas turbine. 

Description : What Are The Causes Of Vibration? a. Unbalanced centrifugal forces in the system. b. Elastic nature of the system. c. Winds may cause vibrations of certain systems such as electricity lines, telephones lines etc. d. All of the above

Last Answer : d. All of the above

Description : If a mass whose moment of inertia is Ic/3 is placed at the free end and the constraint is assumed to be of negligible mass, then the kinetic energy is ______ a) 1/6 Icω 2 b) 1/2Icω 2 c) 1/3Icω 2 d) 1/12Icω 2

Last Answer : a) 1/6 Icω 2

Description : Damp clothes are dried in spin dryers by the action of – (1) centripetal forces (2) centrifugal forces (3) central forces (4) non central forces

Last Answer : (2) centrifugal forces Explanation: The spin dryer is probably the most familiar centrifuge. The spin dryer of a washing machine removes excess water from the clothing by rotating at a high speed. ... pulled to the outside of the spinning portion of the washing machine and away from the clothes.

Description :  In order to keep a body moving in a circle, there exists a force on it that is directed toward the center of the circle. This force is known asA. Centrifugal force B. Centripetal force C. Gravitational Force D. magnetic force

Last Answer : Centripetal force

Description : Damp clothes are dried in spin dryers by the action of (1) centripetal forces (2) centrifugal forces (3) central forces (4) non central forces

Last Answer : centrifugal forces

Description : The speed at which the shaft runs so that the additional deflection from the axis of rotation of the shaft becomes infinite, is known as _________ * 1 point (A) Whirling speed (B) Rotational speed (C) Stabilizing speed (D) Reciprocating speed

Last Answer : (A) Whirling speed

Description : The resistance to the motion of the body is provided by ______ a) Medium of vibration b) Speed of vibration c) Length of the material d) External friction

Last Answer : a) Medium of vibration

Description : Railway tracks are banked on curves so that - (1) Necessary centrifugal force may be obtained from the horizontal component of the weight of the train (2) No frictional force may be produced between the ... the horizontal component of the weight of the train (4) The train may not fall down inwards

Last Answer : (3) Necessary centripetal force may be obtained from the horizontal component of the weight of the train

Description : Railway tracks are banked on curves so that (1) Necessary centrifugal force may be obtained from the horizontal component of the weight of the train (2) No frictional force may be produced between the ... the horizontal component of the weight of the train (4) The train may not fall down inwards

Last Answer : Necessary centripetal force may be obtained from the horizontal component of the weight of the train

Description : The speed at which the shaft runs so that the additional deflection from the axis of rotation of the shaft becomes infinite, is known as _________ A. Whirling speed B. Rotational speed C. Stabilizing speed D. Reciprocating speed

Last Answer : A. Whirling speed

Description : Which of the following statements is/are true for coulomb damping? 1. Coulomb damping occurs due to friction between two lubricated surfaces2. Damping force is opposite to the direction of motion of vibrating body ... 2, 3 and statement 4 c. Only statement 2 d. All the above statements are true

Last Answer : c. Only statement 2

Description : A satellite orbits around the earth due to a.Celestial force b.Gravitational force c.Centrifugal force d.Centripetal force e.All of the above

Last Answer : c. Centrifugal force

Description : Cream gets separated out of milk when it is churned. This is due to– (1) gravitational force (2) centripetal force (3) centrifugal force (4) frictional force

Last Answer : (3) centrifugal force Explanation: During the churning of buttermilk, many particles of curd undergo rotatory motion: Then the particles with less weight experience more centripetal force and hence those particles ... force and so they are forced to the walls of the container away from the centre.

Description : Cream gets separated out of milk when it is churned. This is due to (1) gravitational force (2) centripetal force (3) centrifugal force (4) frictional force

Last Answer : centrifugal force

Description : When the milk is churned vigorously the cream from it is separated out due to (3) Centripetal force (2) Gravitational force (3) Frictional force (4) Centrifugal force

Last Answer : Centrifugal force

Description : A rotary system has a damping coefficient of 40 N-m-sec/rad. The damping torque at a velocity of 2 rad/s, will be A) 20 N-m B) 40 N-m C) 80 N-m D) 100 N-m

Last Answer : C) 80 N-m

Description : A moving body on Earth ordinarily comes to rest by itself because of the (a) Law of inertia (b) Forces of friction (c) Conservation of momentum (d) Gravity

Last Answer : Ans:(b)

Description : If you throw a ball across a field, which forces are most likely to cause it to stop? a) Inertia and Magnetism b) Friction and Gravity c) Wind resistance and magnetism d) Gravity and Inertia

Last Answer : b) Friction and Gravity

Description : Untuned viscous damper ( houdaille Damper) is used with variable speed machine being control by ratio can be given by A) (damper inertia) / (main system inertia) B) (main system inertia) / (damper inertia) ... X damper inertia) / (main system inertia) D) (2 X main system inertia) / (damper inertia)

Last Answer : A) (damper inertia) / (main system inertia)

Description : For a two-rotor system, the length of one shaft (A) is twice the other (B), then what is the relation between the mass moment of inertia of the shafts. A 2I(A) = I(B) B I(A) = 2I(B) C I(A) = I(B) D 2I(A) = 3I(B)

Last Answer : A 2I(A) = I(B)

Description : If the polar moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system? A. Increases 4 times B. Increases 2 times C. Decreases 4 times D. Decreases 2 times

Last Answer : B. Increases 2 times

Description : Increasing which of the following factor would result in increase of free torsional vibration? A. Radius of gyration B. Mass moment of inertia C. Polar moment of inertia D. Length

Last Answer : C. Polar moment of inertia

Description : An increase in the mass moment of inertia results in ________ in vibration frequency. A. increase B. decrease C. unchanged D. none of the above

Last Answer : B. decrease

Description : Untuned viscous damper ( houdaille Damper) is used with variable speed machine being control by ratio can be given by A) (damper inertia) / (main system inertia) B) (main system inertia) / (damper inertia) ... X damper inertia) / (main system inertia) D) (2 X main system inertia) / (damper inertia)

Last Answer : A) (damper inertia) / (main system inertia)

Description : The equation of motion for spring mass system includes A. Inertia Force B. Spring Force C. Both D. Gravitational force

Last Answer : C. Both

Description : Which formula is used to calculate mass moment of inertia (I G ) of a circular rim about the axis through centre of gravity? a. mr 2 /2b. mr 2 /12 c. mr 2 /4 d. mr 2

Last Answer : d. mr 2

Description : Calculate the Polar moment of inertia in m 4 of a single motor system from the following data: C = 8 GN/m 2 , L=9m, I = 600 Kg-m 2 , f=10 Hz a) 0.00027b) 0.00032 c) 0.00045 d) 0.00078

Last Answer : a) 0.00027

Description : f the length inertia is decreased to nine times, then what will be the effect on free torsional vibrations of a single motor system? a) Increases 3 times b) Increases 9 times c) Decreases 9 times d) Decreases 3 times

Last Answer : a) Increases 3 times

Description : If the mass moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system? a) Increases 4 times b) Increases 2 times c) Decreases 4 times d) Decreases 2 times

Last Answer : d) Decreases 2 times

Description : If the polar moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system? a) Increases 4 times b) Increases 2 times c) Decreases 4 times d) Decreases 2 times

Last Answer : b) Increases 2 times

Description : Free torsional vibrations of a single motor system increases with increase in polar moment of inertia. a) True b) False

Last Answer : b) False

Description : Which of the following relation is correct regarding free torsional vibrations of a single motor system? a) Independent of modulus of rigidity b) Independent of polar moment of inertia c) Dependent on mass moment of inertia d) Independent of length of shaft

Last Answer : c) Dependent on mass moment of inertia

Description : Increasing which of the following factor would result in increase of free torsional vibration? a) Radius of gyration b) Mass moment of inertiac) Polar moment of inertia d) Length

Last Answer : c) Polar moment of inertia

Description : . In centrifugal pendulum absorber , the natural frequency in cycle per second can be given by A Fn =N √(R/L) B Fn =1/N √(R/L) C Fn =N/2 √(R/L) D Fn =N2 √(R/L)

Last Answer : A Fn =N √(R/L)

Description : Frequency of centrifugal pendulum absorber is always proportional to A) Oscillating motion B) Transfer motion C) Speed of rotating body D) All of the above

Last Answer : C) Speed of rotating body

Description : Centrifugal absorber is used to reduce A) Centrifugal force in rotating system B) Torsional vibration of rotating system C) Vibration in linear system D) Transverse vibrations

Last Answer : B) Torsional vibration of rotating system

Description : In centrifugal pendulum absorber , the natural frequency in cycle per second can be given by A) Fn =N √(R/L) B) Fn =1/N √(R/L) C) Fn =N/2 √(R/L) D) Fn =N2 √(R/L)

Last Answer : A) Fn =N √(R/L)

Description : From base load operation and from achieving best specific energy consumption point of view, which of the following compressors are suitable? a) Single stage reciprocating compressors b) Centrifugal compressors c) Two stage reciprocating compressor d) Multi stage reciprocating compressor

Last Answer : b) Centrifugal compressors

Description : From the point of lower specific energy consumption, which of the following compressors are suitable for part load operation? a) Two stage reciprocating compressors b) Centrifugal compressors c) Two stage screw compressor d) Single stage screw compressor

Last Answer : a) Two stage reciprocating compressors

Description : The weight of a body is due to  (A) Centripetal force of earth  (B) Gravitational pull exerted by the earth  (C) Forces experienced by body in atmosphere  (D) Gravitational force of attraction towards the centre of the earth 

Last Answer : (D) Gravitational force of attraction towards the centre of the earth 

Description : It is difficult to walk on ice because of ______. (1) absence of friction (2) less inertia (3) more inertia (4) more mass

Last Answer : (1) absence of friction Explanation: It's difficult to walk on ice because there's very little friction between the bottoms of your shoes and the ice. Friction is a force that opposes motion.

Description : Frequency is equal to ______. * 1 point (A) time period (B) 1/time period (C) *time period (D) /time period

Last Answer : (B) 1/time period

Description : δ = (W a 2 b 2 ) / (3 EIL) is the value of deflection for ______ A. simply supported beam which has central point load B. simply supported beam which has eccentric point load C. simply supported beam which has U.D.L. point load per unit length D. fixed beam which has central point load

Last Answer : B. simply supported beam which has eccentric point load

Description : δ = (W a 2 b 2 ) / (3 EIl) is the value of deflection for ______ a. simply supported beam which has central point load b. simply supported beam which has eccentric point load c. simply supported beam which has U.D.L. point load per unit length d. fixed beam which has central point load

Last Answer : b. simply supported beam which has eccentric point load