Problem P3.3: The wind power output per unit area swept by the rotor is 2.4 kw/m 2. Convert this quantity to the dimensions of hp/ft 2.

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1 Chaper 3: Technical Proble-Solving and Counicaion Skill Proble P3.3: The wind power oupu per uni area wep by he roor i.4 kw/. Conver hi quaniy o he dienion of hp/f. Conver o USCS uing he facor fro Table 3.6. kw hp hp f kw f hp f 8 03 Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par.

2 Chaper 3: Technical Proble-Solving and Counicaion Skill Proble P3.4: A world-cla runner can run half a ile in a ie of in and 45. Wha i he runner average peed in /? Ue he converion facor lied in Table 3.5 and 3.6: i 580 f. f L l 3 Conver i o uing hoe facor: i 580 f f Epre he runner peed in /: Alernaively, ue he converion facor: i.609 k. k 000 ( ) Conver i o uing hoe facor: 000 i.609 k k ( ) Epre he runner peed in /: Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par.

3 Chaper 3: Technical Proble-Solving and Counicaion Skill Proble P3.7: (a) How any horepower doe a 00-W houehold ligh bulb conue? (b) How any kw doe a 5 hp lawn ower engine produce? (a) Conver W o kw uing he prefi definiion in Table 3.3. Conver fro kw o hp uing he facor fro Table 3.6: kw hp ( 00 W) hp W kw 0.34 hp (b) Conver fro hp o kw uing facor fro Table 3.6: kw ( 5 hp) kw hp 3.79 kw 03 Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par.

4 Chaper 3: Technical Proble-Solving and Counicaion Skill Proble P3.0: Uphill waer lide are becoing ore popular a large waer park. Uphill peed of rider can reach 9 f/. Epre hi peed in ph. Ue he lengh converion facor lied in Table 3.5 and 3.6: i 580 f Conver fro f/ o ph: f i ph 580 f hr.95 ph 5 03 Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par.

5 Chaper 3: Technical Proble-Solving and Counicaion Skill Proble P3.: A roboic wheeled vehicle ha conain cience inruen i ued o udy he geology of Mar. The rover weigh 408 lb on Earh, (a) In he USCS dienion of lug and lb, wha i he rover' a? (b) Wha i he weigh of he rover a i roll off he lander' plafor (he lander i he proecive hell ha houe he rover during landing)? The graviaional acceleraion on he urface of Mar i.3 f/. (a) The rover' a i he ae on Earh and Mar. On Earh, i weigh 408 lb, and he graviaional acceleraion i 3. f/. By uing w/g 408 lb lb.67 f 3. f ro Table 3.5, he dienion i equivalen o he derived uni of lug,.67 lug By definiion, an objec ha weigh one pound ha a a of one pound a, o 408 lb We double check by uing he definiion in Table lug ( 408 lb) lug lb (b) Since he graviaional acceleraion on Mar i only.3 f/, he weigh becoe f lug f w (.67 lug) Thi group of dienion i dienionally he ae a lb. w 55.9 lb I would no be correc o calculae weigh a he produc of 408 lb and.3 f/, ince he uni would no be dienionally conien Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par.

6 Chaper 3: Technical Proble-Solving and Counicaion Skill Proble P3.6: The propery of a fluid called vicoiy i relaed o i inernal fricion and reiance o being defored. The vicoiy of waer, for inance, i le han ha of olae and honey, ju a he vicoiy of a ligh oor oil i le han ha of a greae. A uni ued in echanical engineering o decribe vicoiy i called he poie naed afer he phyiologi Jean Loui Poieuille who perfored early eperien in fluid echanic. The uni i defined by poie 0. (N )/. Show ha poie i alo equivalen o g/(c ). Epand he derived uni N in er of he SI bae uni: g g c c Apply SI prefie fro Table 3.3: N g c 3 03 Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par.

7 Chaper 3: Technical Proble-Solving and Counicaion Skill Cengage Learning. All Righ Reerved. May no be canned, copied or duplicaed, or poed o a publicly acceible webie, in whole or in par. Proble P3.5: Deerine which one of he following equaion i dienionally conien.,,,, where i force, i a, i diance, i velociy, and i ie. Apply he principle of dienional coniency uing SI uni fro Table 3.: Thi i no dienionally conien. Thi i no dienionally conien. Thi i dienionally conien. Thi i no dienionally conien. Thi i no dienionally conien.