Description : A centrifugal filtration unit operating at a rotational speed of w has inner surface of the liquid (density ρL) located at a radial distance R from the axis of rotation. The thickness of the liquid film is δ and no cake is formed. The ... . ρL (C) ½w 2 . δρL (2R + δ) (D) ½w 2 . R . ρL(R + 2δ)
Last Answer : (C) ½w 2 . δρL (2R + δ)
Description : The maximum value of hoop compression in a dome is given by (A) wR / 4d (B) wR/2d (C) wR/d (D) 2wR/d Where, w = load per unit area of surface of dome R = radius of curvature d = thickness of dome
Last Answer : (B) wR/2d
Description : The displacement of a particle under going rectilinear motion along the x-axis is given by x = 2t3 + 21t2 + 60t + 6 metres. a.27 m/s2 b.18 m/s2 c.36 m/s2 d.9 m/s2 e.107 dynes
Last Answer : d. 9 m/s2
Description : If d is the diameter of the pipe, p is the total internal pressure, f is the permissible tensile stress and n is the effective of the joint, the thickness t of metal pipe, is (A) n (pd/2f) (B) (1/n) (pd/2f) (C) (1/n) (pd/3f) (D) (1/n) (pf/d
Last Answer : (B) (1/n) (pd/2f)
Description : If the strain energy stored per unit volume in a hollow shaft subjected to a pure torque when t attains maximum shear stress fs the ratio of inner diameter to outer diameter, is 17/64 (fs/N) (A) 1/2 (B) 1/3 (C) 1/4 (D) 1/5
Last Answer : (C) 1/4
Description : The local surface conductance for laminar film condensation on vertical surface is (where, t = film thickness) (A) ∝ t (B) ∝ 1/t (C) ∝ √t (D) Independent of 't
Last Answer : (B) ∝ 1/t
Description : The thickness of oxide film is y at time t. If K1, K2 and K3 are the temperature dependent constants, the parabolic law of oxidation is given by (A) y2 = 2k1t + k2 (B) y = k1 ln (k2t + k3) (C) y = k1 t + k2 (D) y = k1t3 + k2
Last Answer : Option A
Description : A thin film having thickness t
Last Answer : (c) Black
Last Answer : C. Black
Description : What causes changes in the colours of the soap or oil films for the given beam of light? (a) Angle of incidence (b) Angle of reflection (c) Thickness of film (d) None of these
Last Answer : Ans:(c)
Description : Light is normally incident on a thin soap film and is reflected. If the wavelength of this light is "L" and the index of refraction of the soap film is "N", complete destructive interference will occur for a film thickness of: w) L / 8N x) L / 4N y) L / 2N z) 3L / 4N
Last Answer : ANSWER: Y -- L / 2N
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 : Critical speed of rotation, N (in rps - rotation per second) of a trammel is equal to (where, g = acceleration due to gravity = 9.81 m/sec 2 and, r = radius of trammel, metre.) (A) (1/2π). √(g/r) (B) (1/π). √(g/r) (C) ½ √(g/r) (D) 2π. √(g/r)
Last Answer : (A) (1/2π). √(g/r)
Description : A closely coiled helical spring of radius R, contains n turns and is subjected to an axial load W. If the radius of the coil wire is r and modulus of rigidity of the coil material is C, the deflection of the coil is (A) WR3n/Cr4 (B) 2WR3n/Cr4 (C) 3WR3n/Cr4 (D) 4WR3n/Cr
Last Answer : (D) 4WR3n/Cr
Description : A closely coiled helical spring of radius R, contains n turns and is subjected to an axial loadW. If the radius of the coil wire is r and modulus of rigidity of the coil material is C, the stress developed in the helical spring is (A) WR/ 3 (B) 2WR/ 3 (C) 2WR/ 2 (D) 4WR/ 2
Last Answer : (B) 2WR/ 3
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 : In hydrodynamic lubrication, film thickness remains unaffected by change in speeds. a) True b) Increase with increase in speed c) Decrease with increase in speed d) Disappear as the speed tends to infinty
Last Answer : b) Increase with increase in speed
Description : A flywheel weighs 400 kg and has a radius of gyration of 30 cm about its axis of rotation. It is mounted on a shaft subjected to a moment of 40 kgm. If the flywheel starts from restits speed after 3 seconds wil be a.10.9 rad/sec b.19.0 rad/sec c.51.2 rad/sec d.3.33 rad/sec e.16.35 rad/sec
Last Answer : d. 3.33 rad/sec
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 : An open-ended cylinder of radius and thickness is subjected to internal pressure . The Young's modulus for the material is and Poisson's ratio is . The longitudinal strain is (A) Zero (B) pr/TE (C) pr/2TE (D) None of these
Last Answer : (A) Zero
Description : If d is the thickness of a concrete pavement, the equivalent radius b of resisting section for an interior loading, is (A) b = d 2 ) - 0.675 d (B) b = d 2 ) + 0.675 d (C) b = d 2 ) - 3.675 d (D) b = d 2 ) - 0.675 d
Last Answer : Answer: Option D
Description : In a shaft, the shear stress is not directly proportional to (A) Radius of the shaft (B) Angle of twist (C) Length of the shaft (D) Modulus of rigidity
Last Answer : (C) Length of the shaft
Description : In a footstep bearing, if the radius of the shaft is doubled, then the torque required to overcome the viscous resistance will be (A) Double (B) Four times (C) Eight times (D) Sixteen times
Description : If V is speed in km/hour and R is radius of the curve, the super-elevation e is equal to (A) V²/125 R (B) V²/225 R (C) V²/325 R
Last Answer : Answer: Option B
Description : If V is the design speed in km/hour and R is the radius of the curve of a hill road, the superelevation (A) e = V / 127 R (B) e = V² / 127 R (C) e = V ²/ 225 R (D) e = V / 225 R
Last Answer : Answer: Option C
Description : If V is speed of a moving vehicle, r is radius of the curve, g is the acceleration due to gravity, W is the width of the carriageway, the super elevation is (A) WV/gr (B) W²V/gr (C) WV²/gr (D) WV/gr²
Description : Which one of the following statements in not correct? [CDS 2003] (a) India is the highest oil-seeds and vegetable oil producing country in the world (b) India is the second largest exporter of ... silk in world (d) India is the second largest producer of three-wheeler motor vehicles in the world
Last Answer : Ans: (c)
Description : A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A → B. Film mass transfer resistance is negligible and pore diffusion of A ... (D) Effectiveness factor for a zero order reaction cannot be 7/8 as it must always be 1
Last Answer : (A) Inner catalyst core of radius R/8 does not participate in reaction (
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 : Power in watts in a shaft having N RPM is given by the equation (a) Power = 2π NT/60 (b) Power = 2π N T (c) Power = 2000 π N T/60 (d) None
Last Answer : (a) Power = 2π NT/60
Description : For the same dimensions of the shaft which of the following has the greater natural frequency? A. Transverse B. Longitudinal C. Depends on thickness D. Depends upon length
Last Answer : B. Longitudinal
Description : For the same dimensions of the shaft which of the following has the greater natural frequency? (A) Transverse (B) Longitudinal (C) Depends on thickness (D) Depends upon length
Last Answer : (B) Longitudinal
Description : For the same dimensions of the shaft which of the following has the greater natural frequency? a) Transverse b) Longitudinal c) Depends on thickness d) Depends upon length
Last Answer : b) Longitudinal
Description : Vernier calipers cannot be used to measure the (A) I.D. & O.D. of the shaft (B) Thickness of parts (C) Depth of holes (D) Clearance between two mating surfaces
Last Answer : Option D
Description : A hollow prismatic beam of circular section is subjected to a torsional moment. The maximum shear stress occurs at (a) inner wall of cross section (b) middle of thickness (c) outer surface of shaft (d) none of these
Last Answer : (c) outer surface of shaft
Description : Maximum shear stress in a hollow shaft subjected to a torsional moment is at the a. Middle of thickness. b. At the inner surface of the shaft. c. At the outer surface of the shaft. d. At the middle surface of the shaft.
Last Answer : c. At the outer surface of the shaft.
Description : If is the internal pressure in a thin cylinder of diameter and thickness , the developed hoop stress, is (A) pd/2t (B) pd/4t (C) pd/t (D) 2pd/t
Last Answer : (A) pd/2t
Description : According to Unwin's formula, the diameter of a rivet of plate of thickness is : (A) d = 6.05 t (B) d = 1.5 t + 4 (C) d = t (D) d = t + 1.5
Last Answer : (A) d = 6.05 t
Description : The width of the flange of a T-beam, which may be considered to act effectively with the rib depends upon (A) Breadth of the rib (B) Overall thickness of the rib (C) Centre to centre distance between T-beams (D) All the above
Description : The width of the flange of a T-beam should be less than (A) One-third of the effective span of the T-beam (B) Distance between the centres of T-beam (C) Breadth of the rib plus twelve times the thickness of the slab (D) Least of the above
Description : The maximum longitudinal pitch in bolted joints, subjected to tensile forces, wherein t = thickness of the plate and D = diameter of bolt, is (a) 32 D (b) 16 D (c) 32 t (d) 16 t
Last Answer : (d) 16 t
Description : A reinforced concrete cantilever porch has thickness t. The main reinforcing steel will be placed (a) At mid-thickness (b) At t/3 from the top (c) Close to the bottom surface (d) Close to the top surface
Last Answer : (d) Close to the top surface
Description : The allowable shear stress in the web of mild steel beams decreases with (a) Decrease in h/t ratio (b) Increase in h/t ratio (c ) Decrease in thickness (d) Increase in height Where h is the height and t is the thickness
Last Answer : (b) Increase in h/t ratio
Description : In a T-beam, the vertical distance between the bottom of the flange and the centre of the tensile reinforcement is (a) Breadth of flange (b) Thickness of flange (c) Breadth of slab (d) Depth of rib
Last Answer : (d) Depth of rib
Description : The thickness of flange in a T-beam is taken equal to the total thickness of the slab, including cover. (a) True (b) False (c) Not known (d) None of these
Last Answer : (a) True
Description : In a T-beam , the breadth of the rib is equal to the (a) Total thickness of the slab, including cover (b) Width of the portion of the beam in the compression zone (c) Width of the portion of the beam in the compression zone (d) All the above.
Last Answer : (c) Width of the portion of the beam in the compression zone
Description : The portion of the slab which acts monolithically with the beam and which resists the compressive stresses, is called _________of flange of the T-beam (a) Length (b) Breadth (c) Thickness (d) Depth
Last Answer : (b) Breadth
Description : Critical speed of shaft having a rotating disc in the middle is A) x/e = 1 / ( r^2 - 1 ) B) x/e = 1 / ( r^2 + 1 ) C) x/e = 1 / ( r^2 - 1^2 ) D) x/e = ( 1 + r) / ( r^2 – 1 )
Last Answer : A) x/e = 1 / ( r^2 - 1 )
Description : While placing of concrete the thickness of each layer for R.C.C. is [ A ] 150 to 300 mm [ B ] 450 mm [ C ] 500 to 750 mm [ D ] 500 mm
Last Answer : [ A ] 150 to 300 mm
Description : Which one of the following sets of parameters should be monitored for determining safe operation of journal bearing? [IES-2000] Oil pressure, bearing metal temperature and bearing vibration (b) ... shaft (c) Bearing metal temperature and oil pressure (d) Oil pressure and bearing vibration
Last Answer : Oil pressure, bearing metal temperature and bearing vibration