The thickness of a laminar boundary layer over a flat plate at two different sections P and Q are 0.8 cm and 2.4 cm respectively. If the section Q is 3.6 m downstream of P, the distance of section P from the leading edge of the plate is (a) 0.32 m (b) 0.22 m (c) 0.40 m (d) 0.53 m

The thickness of a laminar boundary layer over a flat plate at two different sections P
and Q are 0.8 cm and 2.4 cm respectively. If the section Q is 3.6 m downstream of P,
the distance of section P from the leading edge of the plate is
(a) 0.32 m (b) 0.22 m (c) 0.40 m (d) 0.53 m
by

1 Answer

Answer :

Ans: (c) Correct Answer is: 0.45 m
by

Related questions

The laminar boundary layer thickness in zero pressure gradient flow over a flat plate along the x-direction varies as x0.5 while the thickness of turbulent boundary layer varies as (where, x = distance from the leading edge) (A) x1.5 (B) x0.8 (C) x-1.5 (D) x-0.8

Description : The laminar boundary layer thickness in zero pressure gradient flow over a flat plate along the x-direction varies as x0.5 while the thickness of turbulent boundary layer varies as (where, x = distance from the leading edge) (A) x1.5 (B) x0.8 (C) x-1.5 (D) x-0.8

Last Answer : (B) x0.8

Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

The boundary layer thickness at a given section along a flat plate __________ with increasing Reynold's number(A) Increases(B) Decreases(C) Remain same(D) May increase or decrease.

Description : The boundary layer thickness at a given section along a flat plate __________ with increasing Reynold's number. (A) Increases (B) Decreases (C) Remain same (D) May increase or decrease

Last Answer : (B) Decreases

For flow past a flat plate, if ‘x’ is the distance along the plate in the direction of flow, the boundary layer thickness is proportional to (A) √x (B) 1/√x (C) x (D) 1/x Answe

Description : For flow past a flat plate, if ‘x’ is the distance along the plate in the direction of flow, the boundary layer thickness is proportional to (A) √x (B) 1/√x (C) x (D) 1/x Answe

Last Answer : (A) √x

For flow over a flat plate, the ratio of thermal boundary layer thickness, 'xt' and hydrodynamic boundary layer thickness 'x' is equal to (where, NPr = Prandtl number) (A) NPr (B) NPr 1/3 (C) NPr -1 (D) NPr -1/3

Description : For flow over a flat plate, the ratio of thermal boundary layer thickness, 'xt' and hydrodynamic boundary layer thickness 'x' is equal to (where, NPr = Prandtl number) (A) NPr (B) NPr 1/3 (C) NPr -1 (D) NPr -1/3

Last Answer : (B) NPr 1/3

What is the ratio of displacement thickness to nominal thickness for a linear distribution of velocity in the boundary layer on a flat plate? (A) 0.5 (B) 1 (C) 1.5 (D) 2

Description : What is the ratio of displacement thickness to nominal thickness for a linear distribution of velocity in the boundary layer on a flat plate? (A) 0.5 (B) 1 (C) 1.5 (D) 2

Last Answer : (A) 0.5

Pick out the wrong statement. (A) The form drag is dependent upon the occurrence of a wake (B) The shear stress at any given cross-section of a pipe for steady flow (either laminar or turbulent) varies linearly as the radial distance (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity (D) Existence of the boundary layer in fluid flow is because of viscosity of the fluid

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Last Answer : (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity

In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will (A) Decrease gradually (B) Increase gradually (C) Increase rapidly (D) Remain constant

Description : In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will (A) Decrease gradually (B) Increase gradually (C) Increase rapidly (D) Remain constant

Last Answer : (B) Increase gradually

Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect of free convection over a vertical flat plate as (A) Gr0.25, Gr (B) Gr0.25, Gr0.33 (C) Gr, Gr0.25 (D) Gr0.33, Gr0.25

Description : Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect of free convection over a vertical flat plate as (A) Gr0.25, Gr (B) Gr0.25, Gr0.33 (C) Gr, Gr0.25 (D) Gr0.33, Gr0.25

Last Answer : Option A

To prevent movement of moisture from sub-grade to road pavement on embankments about 0.6 m to 1 m higher than water table, the thickness of cut off layer of coarse sand used, is (A) 15 cm (B) 20 cm (C) 30 cm (D) None of these

Description : To prevent movement of moisture from sub-grade to road pavement on embankments about 0.6 m to 1 m higher than water table, the thickness of cut off layer of coarse sand used, is (A) 15 cm (B) 20 cm (C) 30 cm (D) None of these

Last Answer : Answer: Option D

A boat takes 38 hrs for travelling downstream from point p to point q and coming back to a point r midway between p and q. If the velocity of the stream is 8 km/hr and the speed of the boat in still water is 28 km/hr. What is the distance between p and q? A) 720 B) 640 C) 510 D) 450

Description : A boat takes 38 hrs for travelling downstream from point p to point q and coming back to a point r midway between p and q. If the velocity of the stream is 8 km/hr and the speed of the boat in still water is 28 km/hr. What is the distance between p and q? A) 720 B) 640 C) 510 D) 450

Last Answer : ANSWER: A Explanation: Speed downstream = (28 + 8)km/hr = 36 km/hr Speed upstream = (28 – 8)km/hr = 20 km/hr Let the distance between p and q be ‘x’km Then, x/36 + (x/2)/20 = 38 x/36 +x/40 = 38 19x = 13680 X = 720 km Therefore the distance between p and q is 720km

The average heat transfer co-efficient over the entire length of the plate (ha ) and the local heat transfer co-efficient (hL ), in case of heat transfer over a flat plate in laminar zone is related as (A) ha = 0.8hL (B) ha = 2hL (C) ha = hL (D) ha = 5hL

Description : The average heat transfer co-efficient over the entire length of the plate (ha ) and the local heat transfer co-efficient (hL ), in case of heat transfer over a flat plate in laminar zone is related as (A) ha = 0.8hL (B) ha = 2hL (C) ha = hL (D) ha = 5hL

Last Answer : (B) ha = 2hL

A short masonry pillar is 60 cm x 60 cm in cross-section, the core of the pillar is a square whose side is (A) 17.32 cm (B) 14.14 cm (C) 20.00 cm (D) 22.36 cm

Description : A short masonry pillar is 60 cm x 60 cm in cross-section, the core of the pillar is a square whose side is (A) 17.32 cm (B) 14.14 cm (C) 20.00 cm (D) 22.36 cm

Last Answer : (B) 14.14 cm

Minimum thickness of a layer of fine sand required to cut off capillary rise of water completely, should be (A) 40 cm(B) 52 cm (C) 64 cm (D) 76 cm

Description : Minimum thickness of a layer of fine sand required to cut off capillary rise of water completely, should be (A) 40 cm (B) 52 cm (C) 64 cm (D) 76 cm

Last Answer : Answer: Option D

A Bingham fluid of viscosity μ = 10 Pa.s and yield stress, τ0 = 10 KPa, is shared between flat parallel plates separated by a distance of 10 -3 m. The top plate is moving with a velocity of 1 m/s. The shear stress on the plate is (A) 10 KPa (B) 20 KPa (C) 30 KPa (D) 40 KPa

Description : A Bingham fluid of viscosity μ = 10 Pa.s and yield stress, τ0 = 10 KPa, is shared between flat parallel plates separated by a distance of 10 -3 m. The top plate is moving with a velocity of 1 m/s. The shear stress on the plate is (A) 10 KPa (B) 20 KPa (C) 30 KPa (D) 40 KPa

Last Answer : (B) 20 KPa

Consider the fractional knapsack instance n = 4, (p1, p2, p3, p4) = (10, 10, 12, 18), (w1, w2, w3, w4) = (2, 4, 6, 9) and M = 15. The maximum profit is given by (Assume p and w denotes profit and weight of objects respectively) (A) 40 (B) 38 (C) 32 (D) 30

Description : Consider the fractional knapsack instance n = 4, (p1, p2, p3, p4) = (10, 10, 12, 18), (w1, w2, w3, w4) = (2, 4, 6, 9) and M = 15. The maximum profit is given by (Assume p and w denotes profit and weight of objects respectively) (A) 40 (B) 38 (C) 32 (D) 30

Last Answer : (B) 38

Two taps P and Q can fill a cistern in 24 min and 32 min respectively. Both the taps are opened together for a certain time but due to some obstruction the flow of water was restricted to 7/4 of full flow in tap P and 5/3 of full in tap Q. This obstruction is removed after some time and cistern is now filled in 6min from that moment. How long was it before the full flow. A) 8 min B) 3 min C) 5.6 min D) 4.5 min

Description : Two taps P and Q can fill a cistern in 24 min and 32 min respectively. Both the taps are opened together for a certain time but due to some obstruction the flow of water was restricted to 7/4 of full flow in tap P and ... How long was it before the full flow. A) 8 min B) 3 min C) 5.6 min D) 4.5 min

Last Answer : D Let the obstruction remain for X min.  Hence, Part of cistern filled in X min + part of cistern filled in 6 min = full cistern [(7X/4*24)+(5X/3*32)]+[(6/24)+(6/32)] = 1 (12X/96)+(7/16) = 1 12x/96=9/16 Thus, X = 4.5 min.

A boat takes 4hours for traveling downstream from point P to point Q and coming back to point P upstream. If the velocity of the stream is 2km ph and the speed of the boat in still water is 4kmph, what is the distance between P and Q? A.9 km B.7 km C.5 km D.6km

Description : A boat takes 4hours for traveling downstream from point P to point Q and coming back to point P upstream. If the velocity of the stream is 2km ph and the speed of the boat in still water is 4kmph, what is the distance between P and Q? A.9 km B.7 km C.5 km D.6km

Last Answer : Answer- D Basic Formula: Speed of stream = ½ (a-b) km/hr Speed of still water = ½ (a+b) km/hr Explanation: Time taken by boat to travel upstream and downstream = 4 hours Velocity of the stream, ½ (a-b) = 2km/hr a ... + x / 6 = 4 3x + x / 6 = 4 4x = 24 so,x = 6 distance between P and Q = 6km

If h1 and h2 are the differences in level between ground and the formation levels, m is the slope of the sloping sides. D is the distance between the cross sections then, Prismoidal correction for a level section is (A) D/2m(h1 - h2) (B) D/3m(h1 - h2) (C) D/6m(h1 - h2)2(D) D/6m(h1 - h2)3

Description : If h1 and h2 are the differences in level between ground and the formation levels, m is the slope of the sloping sides. D is the distance between the cross sections then, Prismoidal correction for a level section is (A) D/2m(h1 - h2) (B) D/3m(h1 - h2) (C) D/6m(h1 - h2)2 (D) D/6m(h1 - h2)3

Last Answer : (C) D/6m(h1 - h2)2

Pick up the incorrect statement from the following: In a dry dock block made of hard wood, (A) Spacing of the blocks is 1.35 m (B) The lowest block is 1.8 m long 40 cm × 40 cm in cross-section (C) The middle block is 1.6 m long 40 cm × 40 cm in cross-section (D) None of these

Description : Pick up the incorrect statement from the following: In a dry dock block made of hard wood, (A) Spacing of the blocks is 1.35 m (B) The lowest block is 1.8 m long 40 cm × 40 cm in cross-section (C) The middle block is 1.6 m long 40 cm × 40 cm in cross-section (D) None of these

Last Answer : (D) None of these

A leaf spring consists of 3 extra full length leaves and 14 graduated length leaves. The maximum force that can act on the spring is 70kN and the distance between eyes of the spring is 1.2m. Width and thickness of the leaves are 100mm and 12mm respectively. If modulus of elasticity is 207000N/mm², calculate the initial nip. (a) 26.8mm (b) 24.9mm (c) 22.5mm (d)23.1mm

Description : A leaf spring consists of 3 extra full length leaves and 14 graduated length leaves. The maximum force that can act on the spring is 70kN and the distance between eyes of the spring is 1.2m. Width and thickness of the ... /mm², calculate the initial nip. (a) 26.8mm (b) 24.9mm (c) 22.5mm (d)23.1mm

Last Answer : b) 24.9mm

Pick up the correct statement regarding the centre line method of estimating a building (A) Product of the centre line of the walls and area of cross-section of any item, gives total quantity of the item (B) The centre line is worked out separately for different sections of walls of a building (C) The centre line length is reduced by half the layer of main wall joining the partition wall (D) All the above

Description : Pick up the correct statement regarding the centre line method of estimating a building (A) Product of the centre line of the walls and area of cross-section of any item, gives total quantity of the ... length is reduced by half the layer of main wall joining the partition wall (D) All the above

Last Answer : (D) All the above

02. The separation of flow occurs when the hydrodynamic boundary layer thickness is reduced to zero. A) AgreeB) Disagree

Description : 02. The separation of flow occurs when the hydrodynamic boundary layer thickness is reduced to zero. A) Agree B) Disagree

Last Answer : A

When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is: (A) Free convection (B) Entry length problem in laminar forced conduction (developing thermal boundary layer) (C) Mixed convection (both free and forced) (D) Forced convection

Description : When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is: (A) Free convection (B) Entry length problem in laminar forced ... (developing thermal boundary layer) (C) Mixed convection (both free and forced) (D) Forced convection

Last Answer : (C) Mixed convection (both free and forced)

Bernoulli's equation describes the (A) Mechanical energy balance in potential flow (B) Kinetic energy balance in laminar flow (C) Mechanical energy balance in turbulent flow (D) Mechanical energy balance in boundary layer

Description : Bernoulli's equation describes the (A) Mechanical energy balance in potential flow (B) Kinetic energy balance in laminar flow (C) Mechanical energy balance in turbulent flow (D) Mechanical energy balance in boundary layer

Last Answer : (A) Mechanical energy balance in potential flow

In fluid flow, the boundary layer separation cannot occur (A) In case of boundaries experiencing form drag (B) At points of abrupt changes in the flow directions (C) In laminar flow (D) None of these

Description : In fluid flow, the boundary layer separation cannot occur (A) In case of boundaries experiencing form drag (B) At points of abrupt changes in the flow directions (C) In laminar flow (D) None of theseIn ... B) At points of abrupt changes in the flow directions (C) In laminar flow (D) None of these

Last Answer : (D) None of these

Five persons M, N, O, P and Q request a bank for safety lockers. There are only 6 lockers available which are numbered from 52 to 57. The conditions are as follows: I. M’s locker number is 2 less than O’s lockers number. II. Lockers of N and P are next to each other. If N’s locker number is 52 then M’s locker number could be a) 52 or 53 only b) 53 or 54 only c) 54 or 55 only d) 53 or 55 only

Description : Five persons M, N, O, P and Q request a bank for safety lockers. There are only 6 lockers available which are numbered from 52 to 57. The conditions are as follows: I. M's locker number is 2 less than O's lockers ... could be a) 52 or 53 only b) 53 or 54 only c) 54 or 55 only d) 53 or 55 only

Last Answer : c) 54 or 55 only

Five persons M, N, O, P and Q request a bank for safety lockers. There are only 6 lockers available which are numbered from 52 to 57. The conditions are as follows: I. M’s locker number is 2 less than O’s lockers number. II. Lockers of N and P are next to each other. 14. If Q’s locker number is 54 and N’s locker number is greater than Q’s locker number, then which locker number is not allocated? a) locker 52 b) locker 53 c) locker 54 d)locker 56

Description : Five persons M, N, O, P and Q request a bank for safety lockers. There are only 6 lockers available which are numbered from 52 to 57. The conditions are as follows: I. M's locker number is 2 less ... , then which locker number is not allocated? a) locker 52 b) locker 53 c) locker 54 d)locker 56

Last Answer : a) locker 52

Three pipes P, Q and R can fill a tank from empty to full in 40 minutes, 15 minutes, and 30 minutes respectively. When the tank is empty, all the three pipes are opened. P, Q and R discharge chemical solutions X, Y and Z respectively. What is the proportion of the solution Y in the liquid in the tank after 5 minutes? a) 8 / 15 b) 7 / 15 c) 8 / 17 d) 6 / 13 e) 8 / 13

Description : Three pipes P, Q and R can fill a tank from empty to full in 40 minutes, 15 minutes, and 30 minutes respectively. When the tank is empty, all the three pipes are opened. P, Q and R discharge chemical solutions X, Y and Z respectively. ... 5 minutes? a) 8 / 15 b) 7 / 15 c) 8 / 17 d) 6 / 13 e) 8 / 13

Last Answer : a Part of the tank filled by pipe P in 1 minute = 1 / 40 Part of the tank filled by pipe Q in 1 minute = 1 / 15 Part of the tank filled by pipe R in 1 minute = 1/ 30 Here we have to find the proportion of ... together in 5 minute = 5 1/8 = 5/ 8 Required proportion = (1/3) / ( 5/8) = 8 / 15

The minimum thickness of a flat slab is taken (A) L/32 for end panels without drops (B) L/36 for end panels without drops (C) L/36 for interior panels without drop (D) All the above

Description : The minimum thickness of a flat slab is taken (A) L/32 for end panels without drops (B) L/36 for end panels without drops (C) L/36 for interior panels without drop (D) All the above

Last Answer : Answer: Option D

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

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

In case of laminar flow of fluid through a circular pipe, the (A) Shear stress over the cross-section is proportional to the distance from the surface of the pipe (B) Surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder (C) Velocity profile varies hyperbolically and the shear stress remains constant over the cross-section (D) Average flow occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius)

Description : In case of laminar flow of fluid through a circular pipe, the (A) Shear stress over the cross-section is proportional to the distance from the surface of the pipe (B) Surface of velocity distribution is a ... occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius)

Last Answer : (B) Surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder

In horizontal D.P.C, thickness of cement concrete (1 : 2 : 4) is (A) 2 cm (B) 4 cm (C) 6 cm (D) 8 cm

Description : In horizontal D.P.C, thickness of cement concrete (1 : 2 : 4) is (A) 2 cm (B) 4 cm (C) 6 cm (D) 8 cm

Last Answer : Answer: Option B

If the width of a pavement slab is 7.5 m, thickness 20 cm and working stress 1400 kg/cm2 , spacing of 10 mm tie bars for the longitudinal joint, is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Description : If the width of a pavement slab is 7.5 m, thickness 20 cm and working stress 1400 kg/cm2 , spacing of 10 mm tie bars for the longitudinal joint, is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Last Answer : Answer: Option C

If permissible working stresses in steel and concrete are respectively 1400 kg/cm2 and 80 kg/cm2 and modular ratio is 18, in a beam reinforced in tension side and of width 30 cm and having effective depth 46 cm, the lever arms of the section, is (A) 37 cm (B) 38 cm (C) 39 cm (D) 40 cm

Description : If permissible working stresses in steel and concrete are respectively 1400 kg/cm2 and 80 kg/cm2 and modular ratio is 18, in a beam reinforced in tension side and of width 30 cm and having effective depth 46 cm, the lever arms of the section, is (A) 37 cm (B) 38 cm (C) 39 cm (D) 40 cm

Last Answer : Answer: Option D

The formula Q = P - K [1.8T + 32] in which Q is runoff, P is annual rain fall in cm, T is mean annual temperature in centigrade and K is a constant, is known (A) Justin's formula (B) Khosla's formula (C) English formula (D) Vermule's formula

Description : The formula Q = P - K [1.8T + 32] in which Q is runoff, P is annual rain fall in cm, T is mean annual  temperature in centigrade and K is a constant, is known  (A) Justin's formula  (B) Khosla's formula  (C) English formula  (D) Vermule's formula

Last Answer : (B) Khosla's formula 

A motorboat running upstream takes 4 hrs 24 mins to cover a certain distance, while it takes 2hrs to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively? A) 8:3 B) 5:2 C) 3:7 D) 2:4

Description : A motorboat running upstream takes 4 hrs 24 mins to cover a certain distance, while it takes 2hrs to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively? A) 8:3 B) 5:2 C) 3:7 D) 2:4

Last Answer : ANSWER : A Explanation: Let the man's rate upstream be x'km/hr and downstream be y'km/hr Then distance covered upstream by 4hrs 24mints = distance covered by downstream in 2hrs (x * 4 2/5) = y *2 22x/5 = 2y Y = ... = (y+x/2) : (y -x/2) = 16x/10 : 6x/10 = 16x : 6x = 8:3

The stem of a cantilever retaining wall which retains earth level with top is 6 m. If the angle of repose and weight of the soil per cubic metre are 30° and 2000 kg respectively, the effective width of the stem at the bottom, is (A) 51.5 (B) 52.5 (C) 53.5 (D) 54.5

Description : The stem of a cantilever retaining wall which retains earth level with top is 6 m. If the angle of repose and weight of the soil per cubic metre are 30° and 2000 kg respectively, the effective width of the stem at the bottom, is (A) 51.5 (B) 52.5 (C) 53.5 (D) 54.5

Last Answer : Answer: Option C

If S is the potential infiltration, P is rainfall in cm in a drainage of a soil with fair pasture cover, the direct run off Q in cm is given by (A) Q = (P - 0.1 S)²/(P + 0.4 S) (B) Q = (P - 0.2 S)²/(P + 0.6 S) (C) Q = (P - 0.2 S)²/(P + 0.8 S) (D) Q = (P - 0.2 S)²/(P + 0.2 S)

Description : If S is the potential infiltration, P is rainfall in cm in a drainage of a soil with fair pasture cover, the direct run off Q in cm is given by (A) Q = (P - 0.1 S)²/(P + 0.4 S) (B) Q = (P - 0.2 S)²/(P + 0.6 S) (C) Q = (P - 0.2 S)²/(P + 0.8 S) (D) Q = (P - 0.2 S)²/(P + 0.2 S)

Last Answer : Answer: Option C

If three cubes of copper, each with an edge 6 cm, 8 cm and 10 cm respectively are melted to form a single cube, -Maths 9th

Description : If three cubes of copper, each with an edge 6 cm, 8 cm and 10 cm respectively are melted to form a single cube, -Maths 9th

Last Answer : 20.8 cm Let the edge of the single cube be ‘a’ cm. Then, total volume melted = Volume of cube formed ⇒ (6)3 + (8)3 + (10)3 = a3 ⇒ a3 = 216 + 512 + 1000 = 1728 ... Diagonal of the new cube = 3–√a=(3–√×12)3a=(3×12) cm = 20.8 cm (approx.)

A this usual rowing rate, Mohit can travel 12 miles downstream in a certain river in 6 hours less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 24 miles round trip, the downstream 12 miles would then take only one hour less than the upstream 12 miles. What is the speed of the current in miles per hour? A.2.5m/hr B.4 m/hr C.8/3 m/hr D. 5/3m/hr

Description : A this usual rowing rate, Mohit can travel 12 miles downstream in a certain river in 6 hours less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 24 miles round trip, ... current in miles per hour? A.2.5m/hr B.4 m/hr C.8/3 m/hr D. 5/3m/hr

Last Answer : Answer-C Basic Formula: Speed of the stream = ½ (a-b) km/hr Explanation: Let the speed in still water be x m/hr Speed of stream be y m/hr Then, speed upstream = x-y m/hr and Speed downstream = x+y m/hr 12/x-y - ... 1] 3y^2 = 8 y so, y = 8/3 speed of the current = 8/3 m/hr = 2 (2/3) m/hr

M & N do a certain work in 40 days and 24 days respectively. M started the work alone and then after 8 days N joined him till the completion of the work. How long did the work last? a) 16days b) 18days c) 20 days d) 22 days

Description : M & N do a certain work in 40 days and 24 days respectively. M started the work alone and then after 8 days N joined him till the completion of the work. How long did the work last? a) 16days b) 18days c) 20 days d) 22 days

Last Answer : C Work done by M in 8 days = 1/40*8 =1/5 Remaining work = 1-1/5 = 4/5 (M+N)’s 1 day work = 1/40 + 1/24 =(3+5)/120 =8/120 =1/15 Now 1/15 work is done by M & N in 1 day. So 4/5 work will be done by X and Y is, =15 / 1 * 4/5 =12 days Hence total time taken = 12+8 = 20 days

For determining the ultimate bearing capacity of soil, the recommended size of a square bearing plate to be used in load plate test should be 30 to 75 cm square with a minimum thickness of (A) 5 mm (B) 10 mm (C) 15 mm (D) 25 mm

Description : For determining the ultimate bearing capacity of soil, the recommended size of a square bearing plate to be used in load plate test should be 30 to 75 cm square with a minimum thickness of (A) 5 mm (B) 10 mm (C) 15 mm (D) 25 mm

Last Answer : Answer: Option D

Taps P, Q and R can fill a tank in 3, 4 and 5 hours respectively. If all the taps are opened together and after 30 minutes taps Q and R are turned off, find the total time in which the tank is full. A) 2(3/8)hrs B) 1(1/7)hrs C) 2(13/40)hrs D) 3(13/43)hrs

Description : Taps P, Q and R can fill a tank in 3, 4 and 5 hours respectively. If all the taps are opened together and after 30 minutes taps Q and R are turned off, find the total time in which the tank is full. A) 2(3/8)hrs B) 1(1/7)hrs C) 2(13/40)hrs D) 3(13/43)hrs

Last Answer : C In 1 hr P, Q, R = 1/3+1/4+1/5 = 20+15+12/60 = 47/60 Filled in 30m = 47/120 Remaining = 1-47/120 =73/120 Tap P = 3*73/120= 219/120 Total = 219/120+1/2 =219+60 /120= 279/120= 2 13/40 hrs

The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v w = Specific weight of the flowing liquid) (A) 4 (B) 8 (C) 16 (D) 32

Description : The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v w = Specific weight of the flowing liquid) (A) 4 (B) 8 (C) 16 (D) 32

Last Answer : Answer: Option D

The thickness of web for unstiffened plate girder with clear distance‘d’ between the flanges shall be not less than

Description : The thickness of web for unstiffened plate girder with clear distance‘d’ between the flanges shall be not less than

Last Answer : d/85

If a boy rows 8 km downstream in 6 hours and 4 km upstream in 4 hours then how long will he take to cover 16 km in stationary (still) water? A) 8 B) 14 C) 22 D) 16

Description : If a boy rows 8 km downstream in 6 hours and 4 km upstream in 4 hours then how long will he take to cover 16 km in stationary (still) water? A) 8 B) 14 C) 22 D) 16 

Last Answer : Answer: B Explanation: Distance covered in downstream = 8 km Time taken in downstream = 6 hours. Rate of downstream = 8/6=4/3 km/hr Distance covered in upstream = 4 km Time taken in upstream = 4hours. ... 3+1) = 7/6km/hr Time Taken to cover 16 km in still water = 16*6/7=14hrs (approximately)

In the mid-section formula (A) The mean depth is the average of depths of two consecutive sections (B) The area of mid-sections is calculated by using mean depth (C) The volume of the earth work is calculated by multiplying the mid-section area by the distance between the two original sections (D) All of the above

Description : In the mid-section formula (A) The mean depth is the average of depths of two consecutive sections (B) The area of mid-sections is calculated by using mean depth (C) The volume of the ... multiplying the mid-section area by the distance between the two original sections (D) All of the above

Last Answer : (D) All of the above

Boundary layer exists in flow (A) Of real fluids (B) Over flat surfaces only (C) In pipes only (D) Of ideal fluids only

Description : Boundary layer exists in flow (A) Of real fluids (B) Over flat surfaces only (C) In pipes only (D) Of ideal fluids only

Last Answer : (A) Of real fluids