(The densities of metal and of liquid are ρ and σ respectively, and the viscosity of the liquid is η). (a) [(r2g)/(9η)][ ρ -2σ] (b) [(r2g)/(9η)][ 2ρ -σ] (c) [(r2g)/(9η)][ ρ -σ] …
4.5×105 pascal. When the tap is opened the reading of the manometer falls to 4×105 pascal. Then the velocity of flow of water is (a) 7 m/s …
(a) √2h/g (b) √(2hD)/gd (c) √(2hd)/gD (d) …
(a) 9 minute (b) 7 minute (c) 5 minute (d) 3 minute Answer-b (3)
(a) ∝ √h (b) ∝ h (c) ∝ (1/h) (d) Almost independent of h Answer-d (11)
(a) Greater than the coefficient of viscosity for cold air (b) Smaller than the coefficient of viscosity for cold air (c) Same as the coefficient of viscosity for cold air (d) Increases or decreases depending on the external pressure Answer-a …
(a) Remains unchanged (b) Decreases (c) Increases (d) Increases or decreases depending on the external pressure Answer-b (7)
T1 to decrease the height of water to H/η (η>1) ; and it takes T2 time to take out the rest of water. If T1 =T2, then the value of η is (a) 2 (b) 3 (c) 4 (d) 2√2 Answer-c …
(a) Same everywhere (b) More in the middle and less near its banks (c) Less in the middle and more near its banks (d) Increase from one bank to other bank Answer-b (8)
(a) Area decreases (b) Area increases (c) Velocity remains same (d) Area remains same Answer-a (27)
(a) 1 < 2 < 3 (b) 2 < 3 < 1 (c) 3 < 2 < 1 (d) 3 < 1 < 2 Explanation- (c) A stream lined body has less resistance due to air. (15)
(given rate of the flow through single capillary, X=(Π PR4)/ηL (a) (8/9)X (b) (9/8)X (c) (5/7)X …
(a) 3 m/s (b) 6 m/s (c) 12 m/s (d) 8 m/s Answer-c (9)
(a) 9.4 m (b) 4.9 m (c) 0.49 m (d) 0.94 m Answer-d (13)
r1 and r2 are fitted in parallel to the bottom of a vessel. The pressure head is P. What should be the radius of a single tube that can replace the two tubes so that the rate of flow is …
(a) Pressure difference (b) Volume of the liquid collected (c) Length of the capillary tube (d) Inner radius of the capillary tube Answer-d (6)
V=(πQPr4) /ηl where η is coefficient of the viscosity and Q is (a) 8 (b) 1/8 (c) 16 (d) 1/16 Answer-b (15)
(a) Glycerine (b) Water (c) Kerosene (d) All of them at the same time Answer-a (8)
(a) High viscosity (b) Low viscosity (c) Moderate viscosity (d) High density Answer-a (6)
(a) Zero (b) Maximum (c) Equal to critical velocity (d) May have any value Answer-d (2)
(a) Hole number 4 (b) Hole number 3 (c) Hole number 2 (d) Hole number 1 Answer-b (8)
(a) x=√D(H-D) (b) x=√[D(H-D)]/2 (c) x=2√D(H-D) (d) x=4√D(H-D) Answer-c (3)
(a) The water in the tube rises to height v2 /2g (b) The water in the tube rises to height g/2v2 (c) The water in the tube does not rise at all (d) None of these Answer-a (71)
(a) Zero (b) 20.0 cm (c) 10.6 cm (d) 40.0 cm Answer-b (9)
660 kgm–3. The velocity with which gasoline begins to shoot out of the hole is (a) 27.8 m/s (b) 41.0 m/s (c) 9.6 m/s (d) 19.7 m/s Answer-b …
A1 and A2 , are v1 and v2 The difference in the levels of the liquid in the two vertical tubes is h (a) The volume of the liquid flowing through the tube in unit time is A1v1 (b) v2 …
vA and vB , and pressure PA and PB at points A and B respectively (a) vA = vB (b) vB > vA (c) PA = PB (d) PB > PA Answer- a,d (164)
(a) 282.8 cm/sec (b) 432.6 cm/sec (c) 632.6 cm/sec (d) 832.6 cm/sec Answer-a (9)
(a) Upthrust of the air which will be equal to the weight of the air having the same volume as the plane (b) Force due to the pressure difference between the upper and lower surfaces of the wings, created by …
[P/(ρg)]+ h + (1/2)(v2/g) The terms A, B and C are generally called respectively: (a) Gravitational head, pressure head and velocity head (b) Gravity, gravitational head and velocity head (c) Pressure head, gravitational head and velocity head (d) Gravity, pressure …
(a) Move up (b) Move down (c) Move erratically (d) Remain at the same level Answer-b (18)
(a) Bernoulli’s theorem (b) Boyle’s law (c) Archimedes principle (d) Newton’s law of motion Answer-a (9)
(a) Dynamic lift of an aeroplane (b) Viscosity meter (c) Capillary rise (d) Hydraulic press Answer-a (11)
(a) The speed of a particle always remains same (b) The velocity of a particle always remains same (c) The kinetic energies of all the particles arriving at a given point are the same (d) The moments of all the …
A1 and A2 are the cross-sections of the portions of the tube as shown. Then the ratio of speeds v1 / v2 will be (a) A1 / A2 (b) A2/ A1 (c) √A2 / …
(a) Maximum speed and least pressure (b) Maximum pressure and least speed (c) Both pressure and speed maximum (d) Both pressure and speed least Answer-a (4)