### Eamcet - Physics - Fluids

An iron sphere of mass 20 x 10-3 kg falls through a viscous liquid with terminal velocity 0.5 ms-1. The terminal velocity (in ms-1) of another iron sphere of mass 54 X 10-2 kg is :

A.  4.5

B.  3.5

C.  2.5

D.  1.5

There are two holes one each along the opposite sides of a wide rectangular tank. The cross section of each hole is 0.01 m2and the vertical distance between the holes is one meter. The tank is filled with water. The net force on the tank in newton when the water flows out of the holes is: ( Density of water = 1000 kg/m3 )

A.  100

B.  200

C.  300

D.  400

A plastic tube containing few stones is floating in a tank of water. If the stones are unloaded, the water level :

A.  remains same

B.  rises

C.  falls

D.  rises or falls depending on the number of stones unloaded

A force is experienced by cathode rays when they pass through uniform electric field

A.  in the direction of electric field

B.  in the direction opposite to that of electric field

C.  perpendicular to electric field

D.  zero, because the cathode rays do not have the charge

A liquid does not wet the solid surface if the angle of contact is

A.  zero

B.  equal to 450

C.  equal to 900

D.  greater than 900

A horizontal pipe of non-uniform cross-section allows water to flow through it with a velocity 1 ms-1 when pressure is 50 kPa at a point. If the velocity of flow has to be 2 ms-1 at some other point, the pressure at that point should be

A.  50 kPa

B.  100 kPa

C.  48.5 kPa

D.  24.25 kPa

A soap bubble of radius r is blown up to form a bubble of radius 2r under isothermal conditions. If T is the surface tension of soap solution, the energy spent in the blowing

A.  3πTr2

B.  6πTr2

C.  12πTr2

D.  24πTr2

Eight spherical rain drops of the same mass and radius are falling down with a terminal speed of 6 cm-s-1. If they coalesce to form one big drop, what will be the terminal speed of bigger drop (Neglect the buoyancy of the air)

A.  1.5 cm-s-1

B.  6 cm-s-1

C.  24 cm-s-1

D.  32 cm-s-1

Two soap bubbles combine to form a single bubble. In this process, the change in volume and surface area are respectively V and A. If P is the atmospheric pressure, and T is the surface tension of the soap solution, the following relation is true .

A.  4PV - 3TA = 0

B.  3PV - 4TA = 0

C.  4PV - 3TA = 0

D.  3PV + 4TA = 0

An air bubble of radius 1 cm rises from the bottom portion through a liquid of density 1.5 g/cc at a constant speed of 0.25 cms-1. If the density of air is neglected, the coefficient of viscosity of the liquid is approximately, (In Pas) :

A.  13000

B.  1300

C.  130

D.  13

A large tank filled with water to a height h is to be emptied through a small hole at the bottom The ratio of times taken for the level of water to fall from h to h/2 and h/2 to zero is

A.  √2

B.  1/√2

C.  √2-1

D.  1/(√2-1)

Two very wide parallel glass plates are held vertically at a small separation r,and dipped in water surface tension S.Some water climbs up in the gap between the plates. If P0 is the atmospheric pressure of water just below the water surface in the region between the two plates is

A.  P0-(2s/r)

B.  P0+(2s/r)

C.  P0-(4s/r)

D.  P0+(4s/r)

A certain block weights 15N in air. But it weighs only 12N when completely immersed in water. When immersed in another liquid, it weighs 13N. The ratio of relative density of the block and the liquid

A.  1/3

B.  2/3

C.  3/4

D.  3/5

A pipe having an internal diameter ‘D’ is connected to anther pipe of same size. water flows into the second pope through ‘n’ holes, each of diameter ‘d’. If the water in the first pipe has speed ‘V’, the speed of water leaving the second pipe is

A.  D2v/nd2

B.  nD2v/d2

C.  nd2v/D2

D.  d2v/nd2

The loss of weight of a solid when immersed in a liquid at 00C is .If α and β are the volume coefficients of the solid and the respectively, then the loss of weight at C is approximately

A.  W0[1+(α-β)t]

B.  W0[1-(α-β)t]

C.  W0[1-(α+β)t]

D.  W0[2-(α+β)t]