Vapour Pressure

Q.

The area of cross section of a large tank is 0.5 m². It has an opening near the bottom having area of cross section 1 cm². A load of 20 kg is applied on the water at the top. Find the velocity of the water coming out of the opening at the time when the height of water level is 50 cm above the bottom. Take g = 10 m s^-2.

1. (3 - 4) m/s

2. (4 - 5) m/s

3. (3 - 4)cm/s

4. (2 - 3) m/s

Q. When a glass capillary tube of radius 0.015 cm isdipped in water, the water rises to a height of15 cm within it. Assuming contact angle betweenwater and glass to be 0^° , the surface tension ofwater is \lbrack p = 1000 kg m3, g = 9.81 ms21waterP(1) 0.11 Nm-1(2) 0.7 Nm-1(3) 0.072 Nm-(4) None of thesehelid

Q.

The temperature at which the surface tension of water is zero

1. 0°C

2. 277 K

3. 370°C

4. Slightly less than 647 K

Q. A ring is cut out from a Pt tube 8.5 cm internal diameter and 8.7 cm external diameter. It is supported horizontally from a pan of a balance so that it comes in contact with the water in a glass vessel. If an extra 3.47gm wt. is required to pull it away from the water, Surface tension of water in dyne/cm is

Q. a glass capillary sealed at the upper end is of length 0.20m and internal radius 1*10^-5m.the tube is immersed vertically into a liquid of surface tension 7.5*10^-2N/m.to what length the capillary has to immerse so that liquid level inside and outside the capillary becomes same.angle of contact is zero.

Q. A thin walled cylindrical metal vessel (α = 10–3K–1) contains a liquid ( = 10–3K–1). If the vessel and its contents are now heated by 10 K the pressure due to the liquid at the bottom

Q. 26/A pump is designed as a horizontal cylinder with a piston of area A and an outlet orifice of areaa arranged near the cylinder axis. Find the velocity of out flow of the liquid from the pump if thepiston moves with a constant velocity under the action of a constant force F. The density of theiquid is p

Q. 75.WHY IN AN OPEN CONTAINER BOTH PRESSURE AND VOLUME REMAINS CONSTANT ?

Q. Elasticity coefficient of medium??

Q. At 20C temperature in horizontal pipe pressure falls 60 kPa/100 m and water flow in pipe with rate 3 lit/min then what is approximate radius of pipe(Coefficient of viscosity at 20^oC=10^{-3} PI) (1) 2.52 cm (2) 3.64 cm (3) 1.23 cm (4) 4.63 cm

Q. A siphon in use is demonstrated in the following figure. The density of the liquid flowing in siphon is 1.5 $\frac{gm}{cc}$ The pressure difference between the point P and S will be

1. Zero
2. 
3. 
4. Infinity

Q. a capillary tube of radius R is immersed vertically in a liquid such that liquid rises in it to a height h( less than the length of the tube) mass of a liquid rises in the capillary tube is M if the radius of the tube is decreased by 50% then the mass of the liquid that will rise in the tube is

Q. A glass capillary tube of inner diameter 0.28 mmis lowered vertically into water in a vessel. Thepressure to be applied on the water in the capillarytube sothat water level in the tubeis same as that in the vessel is (surfacetension of water 0.07 N/m and atmosphericpressure = 105 N/m2).COOP(2) 99 x 103(1) 103(4) 101 x 103(3) 100 x 103

Q.

When a capillary tube of radius r is dipped in a liquid of density ρ and surface tension S, the liquid rises or falls through a distance

1. 

2. 

3. 

4. 

Q. A †an k is filled by liquid of density ρ upto height H. The avg pressure on walls of containe

Q. a cicular plate of radius 4cm and weght W is made to rest on the surface of water.if a minomum pull of W+F is reqiured to clear the plate off the water surface then find F.Given surface tension of water Sw=0.072Nm

Q.

The excess pressure inside a soap bubble is (Here, S_la is the surface tension between the liquid-air interface).

1. 

2. 

3. 

4. 

Q. The radii of two columns in a U tube are r1 and r2 when a liquid of density P is filled in it.the level difference of the liquid in the two arms in h.The surface tension of the liquid is

Q. The rate of steady flow of a liquid through a capillary tube V under pressure difference P. This tube is connected with another tube of the same length but half radius in (a) series (b) parallel. Find the rate of flow through combination if same pressure difference is maintained across the combination.

Q. With increase in the volume of a closed system the saturation pressure at the given temperature remains same.

1. False
2. True

Q.

a glass rod of radiusof radius 1 mm is inserted symettrically into a glass capillary tube with inside radius 2 mm . then the whole arrangement is brought in contact of the surface of water . surfae tension of water is 7*10^ -2 N/m . to what height will the water rise.(theta -0 deg}

(ans 1.4 cm)

Q. derive the expression for height of which the liquid rise in a capillary tube of radius r. explain what happens when the length of the capillary tube is less than the height up to which the liquid may rise in it.

Q. Will a liquid rise to the same height in different capillary tubes having the same radius of bore but made out of different materials?

Q. If the excess pressure inside a bubble of radius 1.0 cm is balanced by a column of oil 3 mm high, find the surface tension of the bubble. Specific gravity of liquid = 0.8.

Q. 2 glass capillary tubes of 1mm radius are put in mercury and water.
compare liquid levels of the 2 tubes sp gr=13.6 surface tension of water=73*10^-3 n/m surface tension of mercury=473*10^-3 n/m and angle of contact 139 deg

Q.

A U-tube contains water and methylated spirit separated by mercury. The mercury columns in the two arms are in level with 10.0 cm of water in one arm and 12.5 cm of spirit in the other then find difference in the height of mercury column?