Registered Registered Master Electrician (REE) Review
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The viscosity viscosity of water at 70C is 0.00402 0.00402 poise poise and its specific specific gravity is is 0.978, determine determine its abso!te abso!te viscosity viscosity in "a # s and $inematic viscosity in m2%s and sto$es& a. 4.02 ' 10() "a #s , 4.11 '10(7 sto$es b. 4.02 ' 10(4 "a #s , ).11 '10(* sto$es c. 4.02 x 10-4 Pa –s , 4.11 x10 -3 stokes d. ).02 ' 10(4 "a #s , 4.11 '10(* sto$es + i i!i !id d of visc viscos osit ity y ).2 ).2 ' 10() bf # sec%ft2 is fowing in a rectang!ar d!ct. The e!ation of the symmetrica veocity -ft%s is appro'imatey / 0.*y0.7 ft%s where y is in inches. Comp!te the veocity gradient at y * inches from the wa, and the shear stress of the f!id at that point. a. .42 x 10-! "#$%$t2 b. 8.42 ' 10() bf%ft2 c. 7.42 ' 10() bf%ft2 d. .42 ' 10() bf%ft2 + 4.9 c!bic c!bic feet of water water are compres compressed sed to )000 psig. psig. hat hat is the vo!me vo!me decrease decrease if the tempera temperat!r t!re e is 03& +ss!me the b!$ mod!!s of easticity of *11 000 psi. a. – 0.0&'' $t3 b. # 0.088 ft ft* c. # 0.0)88 ft* d. # 0.0488 ft ft* stimate stimate the height height to which which the water wi wi rise in a capia capiary ry t!be of diameter diameter ) mm if the s!rface s!rface tension tension is 0.0728 5%m and the contact ange is 0 degree& a. 0.00*94 m b. 0.00494 m c. 0.00!4 ( d. 0.0094 m + vac!! vac!!m m p!mp p!mp is !sed !sed to drai drain n a foo foode ded d mine mine shaft shaft of 83 83 -20C -20C wate water. r. The The vapo vaporr press! press!re re at this this temperat!re is 0.*4 psi -2.*4 $"a. The p!mp is incapabe of ifting the water higher than 400 inches -0.1m. Comp!te the atmospheric press!re. a. 2.909 $" $"a #. 3.0) kP kPa c. 4.909 $"a d. ).909 $" $"a Conver Convertt a vac!!m vac!!m press! press!re re of 110 mm of merc!ry into into abso!t abso!te e press!re press!re if atmosphe atmospheric ric press! press!re re is 10.) meters of water. a. m 62 b. 7 m 62 c. 8 m 62 *. ( H 2+ + hydra! hydra!ic ic press press is !sed to raise raise an 80 $5 cargo tr!c$. tr!c$. f oi of specifi specific c gravity gravity of 0.82 acts acts on the piston piston !nder press!re of 10 "a. hat is the diameter of piston re!ired& a. 100 (( b. 110 mm c. 120 mm d. 1*0 mm f atmosp atmosphe heri ric c air 14.7 14.7 psia psia and and 03 03 at sea eve eve,, what what is the the pres press! s!re re at 1200 12000 0 ft atit! atit!de de if air air is incompressibe& 5ote: ; 03< the density of air is 0.07* bm%ft*< "1 14.7 psia. a. .*4 psia b. 7.*4 psia c. '.34 sa d. 9.*4 psia
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Registered Master Electrician (REE) Review 9.
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f atmospheric air 14.7 psia and 03 at sea eve, what is the press!re at 12000 ft atit!de if air is compressibe& 5ote: ; 03< the density of air is 0.07* bm%ft*< "1 14.7 psia. a. .)4 psia b. 7.)4 psia c. 8.)4 psia *. .!4 sa f the press!re in the air space above an oi -=> 0.7) s!rface in a cosed tan$ is 11) $"a abso!te. hat is the press!re 2 meters beow the s!rface& a. 12.&! kPa b. 1*9.7) $"a c. 149.7) $"a d. 1)9.7) $"a There are two f!ids in an open end manometer. 3!id 1 is gycerin -12.4 $5%m*, 70 mm beow the cosed end and f!id 2 is carbon tetrachoride -1).)7 $5%m * which is 1)0 mm above f!id. f the open end is e'posed to the atmosphere at 101.*2) $"a, what is the abso!te press!re at the cosed end of the manometer if it is occ!pied by f!id 1& a. 102.&2! kPaa b. 112.792) $"aa c. 122.792) $"aa d. 1*2.792) $"aa + soid materia in a c!be shape foats in oi of density 800 $g%m* with one third of the boc$ o!t of the oi. hat is the b!oyant force on the c!be whose edge is 0.7)m& a. 22! k$ b. 2*) $gf c. 24) $gf d. 2) $gf +n iceberg having specific gravity of 0.92 foating on sat water of specific gravity of 1.0*. f the vo!me of the ice above the water s!rface is 1000 m*, what is the tota vo!me of the ice& a. 3)3.)4 (3 b. 94*.4 m* c. 9)*.4 m* d. 9*.4 m* + vertica rectang!ar gate 1.) m wide and * m high s!bmerged in water with its top edge 2m beow the water s!rface, find the tota press!re acting on one side of the gate and its ocation from the bottom. a. 144.)1 $5, 1.28)7 m #. 1!4.!1 kN, 1.2'!& ( c. 1)4.)1 $5, 1.*8)7 m d. 1)4.)1 $5, 1.48)7 m +ss!ming a norma barometric press!re, how deep in the ocean is the point where an air b!bbe, !pon reaching the s!rface, has five times its vo!me than it had at the bottom& a. 40.11 ( b. 4*.11 m c. 4).11 m d. 4.11 m + cyindrica tan$ having a diameter of 1.) m and height of 4 m is open at one end and cosed at the other end. t is paced beow the water s!rface with its open end down. 6ow deep beow the water s!rface sho!d the tan$ be paced if the depth of the water inside the tan$ is 1.8 m& a. 4.2) m b. ).2) m c. ).2! ( d. 7.2) m ater having a $inematic viscosity ?$ 1.* ' 10( m2%s fows in a 100 mm diameter pipe at a veocity of 4%) m%s. Comp!te the @eynods n!mber. a. 34)1!3.'! b. *)1)*.8) c. *1)*.8) d. *71)*.8)
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Registered Master Electrician (REE) Review 18. i has a specific gravity of 0.80 fows in a 200 mm diameter pipe. 3ind the critica veocity if ? 8.14 ' 10(2 "a # s. a. 1.01&! (%s b. 1.117) m%s c. 1.217) m%s d. 1.*17) m%s 19. +n engineer needs to deiver 1)0 ft*%min of water in a ro!nd pipe in s!ch a way that the fow in the pipe remains aminar. f the critica @eynods n!mber is 2000, what is the diameter of the pipe necessary to ens!re aminar fow& -5ote: $inematic viscosity of water is 4.7) ' 10 () ft2%s. +ss!me that the fow in the pipe wi be !niform. a. 2*.) ft #. 33.! $t c. 4*.) ft d. )*.) ft 20. The diameter of the pipe at the arger end is 0.)0 cm and at the smaer end is 0.20 cm, the arger and smaer ends ocated 7 meters and * meters respectivey, from the dat!m ine. f the arger end, the veocity is 1.2 m%s and the press!re is )200 $5%m2, comp!te the press!re at the smaer end. a. .) m%s #. &.! (%s c. 8.) m%s d. 9.) m%s 21. f the veocity of fow in a 7) mm diameter fire hose is 0.)0 m%s. hat is the veocity in a 2) mm diameter Aet iss!ing from a noBBe attached at the end of the pipe& Comp!te aso the power avaiabe in the Aet. a. 4.! (%s, 22.4 / b. 4.) m%s, *2.4 c. ).) m%s, 22.4 d. ).) m%s, *2.4 22. +n opening is made at the bottom of a dam 144 ft high. 3ind the appro'imate veocity of the water that wi fow thro!gh the opening if friction is negected. a. .* ft%s b. 7.* ft%s c. 8.* ft%s *. ).3 $t%s 2*. hat is the veocity of so!nd in 1)03 water if its density is 1.2 bm%ft* and the !$ mod!!s of asticity is *28000 psi& a. 48).0 ft%s b. 478).0 ft%s c. 488).0 ft%s *. 4'!.0) $t%s 24. + cyindrica 1 ft diameter, 4 ft high tan$ contains * ft of water. hat rotationa speed is re!ired to spin water o!t to the top& a. 12.7 rad%s #. 22.& a*%s c. *2.7 rad%s d. 42.7 rad%s
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