A mercury (specific gravity = 13.6) manometer connected across an orificemeter fitted in a pipe shows a manometer reading of 2 cms. If the manometer liquid is changed to carbon tetrachloride (specific gravity = 1.6), then for the same flow rate of water the new manometer reading will be _________

A Differential manometer is connected at the points A and Bat the centre of two pipes. The pipe A(left limb) contains a liquid of specific gravity = 1.5 while pipe B (right limb)contains a liquid of specific gravity 0.85. The pressure at A and B are .5 kgf/cm2 and 1.2 kgf/cm2 respectively. Find the difference in level of mercuru in the differential manometer. A is 2.5m above B and 5 m above the mercury in its own limb. B is 2.5 m above the mercury level in limb A.

A

12.7 cm

B

contains a liquid of specific gravity = 1.5 while pipe B (right lim[contains a liquid of specific gravity 0.85. The pressure at A and B are .5 kgf/cm2 and 1.2 kgf/cm2 respectively. Find the difference in level of mercuru in the differential manometer. A is 2.5m above B and 5 m above the mercury in its own limb. B is 2.5 m above the mercury level in limb A. a) 12.7 cm [ 25.5 cm

C

6.28 cm

D

10.85 cm

The right limb of a simple U-tube manometer containing mercury is open to the atmosphere while the lift limb is connected to a pipe in which a fluid of specific gravity 0.85 is flowing. The centre of the pipe is 14 cm below the level of mercury in the right limb.Evaluate the pressure of fluid flowing in the pipe if the difference of mercury level in the two limbs is 22 cm.

A

2.86 N/cm2

B

5.73 N/cm2

C

1.43 N/cm2

D

None of the mentioned

A tank has an inlet and outlet pipe. The inlet pipe fills the tank completely in 2 hours when the outlet pipe is plugged. The outlet pipe empties the tank completely in 6 hours when the inlet pipe is pluggeed. If there is a lekage also which is capable of draining out the liquid from the tank at half of the rate of outet pipe,them what is the time taken to fill the emty tank when both the pipes are opened?

A

3 hours

B

4 hours

C

5 hours

D

None of these

Two pipes A and B can fill an empty cistern in 18 and 27 hours, respectively. Pipe C can drain the entire cistern in 45 hours when no other pipe is in operation. Initially, when the cistern was empty Pipe A and Pipe C were turned on. After a few Pipe A was turned off and Pipe B was turned on instantly. In all, it took 55 hours to fill the cistern. For how many hours was Pipe B turned on?

A

50

B

45

C

27

D

30

A water line is buried underground in dry soil that has an assumed initial temperature of 4.5 degree Celsius. The pipe may have no flow through it for long period of time, yet it will not be drained in order that no freezing occurs, the pipe must be kept at a temperature not lower than 0 degree Celsius. The pipe is to be designed for a 30 hour period at the beginning of which the soil surface temperature suddenly drops to – 17 degree Celsius. Workout the minimum earth covering needed above the water pipe so as to prevent the possibility of freezing during 36 hour cold spell. The soil in which the pipe is buried has the following properties Density = 640 kg/m3 Specific heat = 1843J/kg degree Thermal conductivity = 0.345 W/m degree

A

0.25 m

B

0.35 m

C

0.45 m

D

0.55 m

The pressure drop per unit length of pipe incurred by a fluid 'X' flowing through pipe is $$\Delta {\text{p}}.$$ If another fluid 'Y' having both the specific gravity & density just double of that of fluid 'X', flows through the same pipe at the same flow rate/average velocity, then the pressure drop in this case will be

A

$$\Delta {\text{p}}$$

B

$$2\Delta {\text{p}}$$

C

$$\Delta {{\text{p}}^2}$$

D

$$\frac{{\Delta {\text{p}}}}{2}$$

A water tank with 64-gallon capacity is filled by pipe A and emptied by pipe B. If the rate of water flow through pipe A is 2 gallons per hour, how many gallons per hour should flow through pipe B so that when both pipes are open, the initially empty tank shold be full in exactly 96 hours?

A

3/8

B

4/3

C

2/3

D

8/3

A circular pipe of radius 7 cm is used for water flow transmission. This pipe is moulded into another pipe with a square cross-section keeping the length same. (Ignore the thickness of the pipe). Calculate the hydraulic diameter of the moulded pipe. (Take π = 22/7).

A

11 cm

B

7 cm

C

3.5 cm

D

22 cm

The Reynolds number is found out for a flow in a circular pipe. This circular pipe is moulded into a square pipe, keeping length of the pipe same. Ignore the thickness of the pipe. The Reynolds number changes by __________

A

57% decrease

B

57% increase

C

43% decrease

D

43% increase

The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, $$l$$ = Length of pipe, v = Velocity of the liquid in the pipe, $$\mu $$ = Viscosity of the liquid and w = Specific weight of the flowing liquid)

A

$$\frac{{4\mu {\text{v}}l}}{{{\text{w}}{{\text{d}}^2}}}$$

B

$$\frac{{8\mu {\text{v}}l}}{{{\text{w}}{{\text{d}}^2}}}$$

C

$$\frac{{16\mu {\text{v}}l}}{{{\text{w}}{{\text{d}}^2}}}$$

D

$$\frac{{32\mu {\text{v}}l}}{{{\text{w}}{{\text{d}}^2}}}$$