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1 Viscosity. The popety of viscosity in gas is due to ) Cohesive foces between the moecues ) Coisions between the moecues ) Not having a definite voume ) Not having a definite size. When tempeatue is inceased a) Viscosity of the gas inceases b) Viscosity of the gas deceases c) Viscosity of the iquid deceases d) Viscosity of the iquid inceases ) (a) and (c) ae tue ) (b) and (c) ae tue ) (b) and (d) ae tue ) (a) and (d) ae tue. The Reynods s numbe fo fuid fow in a pipe does not depend on (a) The ength of the pipe (c) The viscosity of the fuid (b) The diamete of the pipe (d) The density of the fuid () a, b () a, c () b, d () a, d. [A]: Heavy machineies equie high viscous oi whie ight machineies equie ow viscous oi. [R]: The intena fiction deveoped in the eative motion depends upon viscosity.. If both Assetion and Reason ae tue and Reason is coect expanation of Assetion.. If both Assetion and Reason ae tue but Reason is not the coect expanation of Assetion.. If Assetion is tue but Reason is fase.. If both Assetion and Reason ae fase.

2 5. [A]: The bood pessue in humans is geate at the feet than at the bain. [R]: Pessue of iquid at any point is popotiona to height, density of iquid and acceeation due to gavity.. If both Assetion and Reason ae tue and Reason is coect expanation of Assetion.. If both Assetion and Reason ae tue but Reason is not the coect expanation of Assetion.. If Assetion is tue but Reason is fase.. If both Assetion and Reason ae fase. 6. [A]: Duing takeoff of an aeo pane, veocity of ai above the wing is geate than beow the wing. [R]: Benoui s pincipe is based on aw of consevation of enegy.. If both Assetion and Reason ae tue and Reason is coect expanation of Assetion.. If both Assetion and Reason ae tue but Reason is not the coect expanation of Assetion.. If Assetion is tue but Reason is fase.. If both Assetion and Reason ae fase. 7. Which of the foowing ae/is not pactica exampe of capiaity action? ) If one end of a towe is dipped in wate fied vesse, then afte some time the entie towe is wet. ) Witing nib is spit in the midde. ) The designing of the aeo pane wings such that the cuvatue of its uppe suface is geate than that of the owe. ) Poughing of fieds heps etain moistue in them.

3 8. When an ai bubbe moves up fom the bottom of a deep is ake, a) Its acceeation is constant. b) Its acceeation deceases and becomes zeo. c) Its veocity deceases and becomes constant. d) Its veocity inceases and becomes constant. ) a, c ) a, d ) b, c ) b, d 9. Match the foowing in List I and List II. List I List II a) Pasca s aw e) Ventuimete b) Achimedes s pincipe f) Effux veocity c) Benoui s equation g) Hydauic pess d) Toicei s theoem h) Hygomete ) a h, b e, c f, d g ) a h, b g, c e, d f ) a g, b h, c e, d f ) a g, b e, c f, d h 0. A): The shape of an automobie is so designed that its font esembes the steam ine patten of the fuid though which it moves. R): The esistance offeed by the fuid is maximum. ) Both A and R ae tue and R is the coect expanation of A. ) Both A and R ae tue and R is not the coect expanation of A. ) A is tue and R is fase. ) A is fase and R is tue.. A): Machine pats ae jammed in winte. R): The viscosity of ubicant used in machine pats incease at ow tempeatue. ) Both A and R ae tue and R is the coect expanation of A. ) Both A and R ae tue and R is not the coect expanation of A.

4 ) A is tue and R is fase. ) A is fase and R is tue.. Aange the foowing iquids in the inceasing ode of thei viscosity. a) Casto oi b) Mecuy c) Benzene d) Gycein ) a, b, c, d ) b, a, d, c ) d, a, c, b ) c, b, a, d. The tangentia foce (o) viscous foce on any aye of the iquid is diecty popotiona to veocity gadient. Then the diection of veocity gadient is. Pependicua to the diection of fow of iquid. Paae to the diection of fow of iquid. Opposite to the diection of fow of the iquid. Independent of the diection of fow of iquid.. An idea fuid is fowing though fou tubes a, b, c, d of adii in the atio : 7: : with veocities in the atio : : 5: 5 when maintained at diffeent pessues. The ascending ode of the amount of fuid fowing though the tubes pe second is ) a, d, c, b ) b, c, d, a ) c, p, b, a ) b, c, d, a 5. A squae pate of 0. m side moves paae to a second pate with a veocity of 0. m/s, both pates being immesed in wate. If the viscous foce is 0.00 N and the coefficient of viscosity is 0.0 poise, distance between the pates in m is ) 0. ) 0.05 ) ) Wate is aowed to fow though a capiay tube of ength 0cm and diamete mm unde a constant pessue diffeence of 6.5 cm of wate eve. If 0.6 ites of wate fows in minute, its coefficient of viscosity is, ) poise ) poise ) poise ) 0.97 poise

5 7. A meta ba of adius '' and density d taves with a temina veocity 'v' in a iquid of density d/. The temina veocity of anothe ba of adius '' and density 'd' in the same iquid is ) v ) v ) v ) v 8. Two meta sphees of densities in the atio : and diamete in the atio : ae eeased fom est in two vetica iquid coumns of coefficients of viscosity in the atio :. If the viscous foce on them is same, then the atio of thei instantaneous veocities is ) : ) : ) : ) 8: 9. The temina veocity of a sma ba faing in a viscous iquid depends upon i) its mass m ii) its adius iii) the coefficient of viscosity of the iquid and iv) acceeation due to gavity. Which of the foowing eations is dimensionay tue fo the temina veocity V ) Kmg ) Kmg ) Kmg ) K mg 0. The coefficients of viscosity of two iquids ae in the atio :. What is the atio of the voumes of iquid coected in the same time using the same vesse competey fied with iquids of densities in the atio : 5? (The capiay tubes used have the same ength and same boe diamete. ) 8: 5 ) 6: 5 ) 5: 6 ) 5: 8. When wate (h0.0 poise) and benzene (h poise) ae aowed to fow though capiay tube, it was found that the same amount of iquids ae coected in the same time. But the pessues that caused the fow ae diffeent. The pessue on wate is 0.05 atmosphee, the coesponding pessue fo benzene in atmosphee is ) ) ) ) 9.75

6 . Two ain dops each the eath with thei temina veocities in the atio :9. The atio of thei adii is ) :9 ) : ) : ) 9:. A soid ubbe ba of density d and adius R fas though ai. Assume that the ai esistance acting on the ba is KRV, whee V is veocity of the ba and K is a constant. The temina veocity attained by the ba is ) π R dg / K ) π Rdg / K ) π Rd g / K ) None. In a panet a sucose soution of coefficient of viscosity 0.005N-Sm - is diven at a veocity of 0 - ms - though xyem vesses of adius µ m and ength 5 µ m. The hydostatic pessue diffeence acoss the ength of xyem vesses in Nm - is ) 5 ) 8 ) 0 ) 5 5. Two capiay tubes of adius but of engths and ae fitted in paae to the bottom of a vesse. The pessue head is P. What shoud be the ength of a singe tube that can epace the two tubes so that the ate of fow is same as befoe? ) + ) + + ) 6. In the above if the engths ae same and adii ae and then ) ( ) + ) ( ) + ) ( ) + ) ( ) + ) + 7. The ate of steady voume fow of wate though a capiay tube of ength '' and adius '' unde a pessue diffeence of P is V. This tube is connected with anothe tube of the same ength but haf the adius in seies. Then the ate of steady voume fow though them is (The pessue diffeence acoss the combination is P) ) V 6 ) V 7 ) 6V 7 ) 7V 6

7 8. In the above if the tubes ae paae; the ate of fow is given by ) V 6 ) V 7 ) 6V 7 ) 7V 6 9. A cyindica vesse of height h is kept maintained with fu of wate. The capiay tube of equa ength and adii is aanged at h, h, h fom the top. The ength of the equivaent tube of same adius which can epace these thee tubes, h that is aanged at fom the top. ) L ) L ) L ) 6 5 L 0. We have two (naow) capiay tubes T and T. Thei engths ae and and adii of coss-section ae and espectivey. The ate of fow of wate unde a pessue diffeence P though tube T is 8cm /sec. If and, what wi be the ate of fow when the two tubes ae connected in seies and pessue diffeence acoss the combination is same as befoe ( P) ) cm /sec ) (6/) cm /sec ) (8/7) cm /sec ) None of these Key ) ) ) ) 5) 6) 7) 8) 9) 0) ) ) ) ) 5) 6) 7) 8) 9) 0) ) ) ) ) 5) 6) 7) 8) 9) 0)

8 Hints dυ F A dx dx 0 dx x 0 - m m π P Q 8 π ( h ρ g) Q (0.) ( d ρ ) g υt 9 υt ( ρ σ ) d υ υ d t υ t v 9.7 x Poise 8. 6π υ 6π υ υ. υ

9 : 9. i) kmg M ( LT ) LT ( ML T )( L) 0. ii) iii) iv) kmg M LT L L T ( )( ) ( ML T ) kmg M LT ML T M L T L ( )( ) ( ) k ( L)( ML T ) mg M ( LT ) π P V. t 8 π ( hdg) V. 8 V d V d V V. 6:5 s 5 π P. V. t 8 P co nst P P. υ t υt υ t 9 t L T atm P

10 . F KRV. Mg KRV t π R dg KRV t π υt K π P Q 8 R dg π P Aυ P 5 N/m 0 5. Q Q + Q π P Q 8 + ( ) / P Q 8 π + + P V Q π

11 8. V πp 8 ; P V π V V V + V 9. V V + V + V 0. P P + P + P h L L V π P 8cm 8 sec Fo composite tube Pπ V 8 + πp 8 V 7V V h h + + h L 6 cm 8 sec o