WATER WORLDEssential QuestionBuoyant ForceProblem Solving ActivityConclusions & AssignmentMystery Revealed
What makes one stand out?
TITANICLength over-all: 882.5 ft Gross tonnage: 46, 329 tons Net tonnage: 24, 900 tons Depth: 59.5 ft
F2PA = FA /APB = FB /AP1= F1 /AFAF1P2 = F2 /AFB
FA= FBHorizontal ForcesThus, Fx =FA+ (-FB) =0Vertical ForcesP1 P2Then, F1 F2
Thu s, Fy =F1+ (-F2) =0F1+ (-F2) =FBFB = F1 - F2 ORBUOYANT FORCE The Net Upward Force ex erted by a fluid on a submerged or immersed object.
FB = P1A - P2A = ( P1 P2 ) A FB = P1A - P2A FB = F1 - F2 FB = P1A - P2AORFB = ( P1 P2 ) A
Note : The difference in pressure at two different elevations in a fluid is P1 - P2 = g ( y 2 y 1 ) FB = ( P1 P2 )A
By substitutionFB = (P1 P2)AFB = g(y2 y1)AV block= (y2 y1)A = Vfluid displacedThus,FB = g(y2 y1)AFB = fluidgVfluid
FB = fluidgVfluidFB = mfluidgdisplaced fluidFB = W
FB = Wdisplaced fluidARCHIMEDES PRINCIPLE An immersed object is buoyed up by a force equal to the weight of the fluid it displaces.
ARCHIMEDES PRINCIPLEFB = W in air W in water
PROBLEM SOLVING ACTIVITYMATERIALS: clay graduated cylinder Electronic weighing scale beakerCalculator basin
PROBLEM SOLVING ACTIVITYTASK 1: Determine the buoyant force on ball of clay submerged in water. TASK 2: Determine the buoyant force on basin-like clay immersed in water.
BALL OF CLAYBASIN-LIKE CLAY*Weight of ball of clay:W = mg*Weight of the displaced fluidm=V
W = mg*Weight of basin-like clay:W = mg*Weight of the displaced fluidm=V
W = mgBUOYANT FORCE = Weight of displaced fluid
CONCLUSIONSIf the weight of an object is greater than the weight of the displaced fluid or BUOYANT FORCE, object sinks in the fluid.If the weight of an object is less than the weight of the displaced fluid or BUOYANT FORCE, object floats in the fluid.
ASSIGNMENT1. Read more about buoyant force.2. Research how Archimedes Principle is applied in swimming and in sea transport.3. Research on good internet sites about buoyancy and Archimedes Principle.
Navaza, Delia C. & Valdes, Bienvenido J. (2004). Physics. Quezon Avenue, Quezon City: Phoenix Publishing House Inc.Giancoli, Douglas C. (1998). Physics: Fifth edition. 23 First Lok Yang Road, Singapore: Pearson Education South Asia Pte. Ltd.REFERENCE LIST
Hewitt, Paul G. (2002). Conceptual Physics: Ninth edition. 23 First Lok Yang Road, Singapore: Pearson Education South Asia Pte. Ltd.Cameron, James (Producer and Director). (June 23, 1999). Titanic [Motion picture]. Hollywood: Columbia Pictures.REFERENCE LIST
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