Center of Pressure

Introduction:
The point in a body at which the resultant pressure acts when the body is immersed in a fluid.

The apparatus for center of pressure.

Objective:
The object of this experiment was to calculate the hydrostatic force a fluid exerts on a submerged plane surface and then compare the experimental hydrostatic force to the theoretical hydrostatic force.

Theory:
The apparatus defining the physical dimensions, this nomenclature will be used throughout this theory. Whilst the theory for the partly submerged and fully submerged plane is the same, it will be clearer to consider the two cases separately. The apparatus can make the calculation center of pressure.
A fluid at rest is said to be a static condition. the fluid particle experiences a constant pressure on all sides acting inward towards a single point at its center. The horizontal x and y components of the pressure are equal and opposite and have a net sum of zero. It can be said that the pressure does not change in the horizontal direction,

The apparatus for center of pressure.

Apparatus: * The hydraulics bench * The hydrostatic pressure apparatus * A set of weights * A jug * Calipers or ruler, for measuring the dimensions of the quadrant
For siphoning * A measuring cylinder, or other container of water of similar height to the hydrostatic pressure tank. * A length of small bore flexible tubing.

Method 1. Place the center of pressure apparatus on a level surface. This is important for obtaining an accurate force balance scenario. 2. Add weight to the weight hanger of the center of pressure apparatus. For example, add 50 grams. the hanger can be found on the far left of the apparatus. 3. Pour water into the torus until the added weight of the water balances the lever arm about the pivot to a horizontal position. 4. Repeat steps 2 through 4 until the weight is 300 grams.

Result Height of quadrant D(m) | Width of quadrant B(m) | Length of balance L(m) | Quadrant to pivot H(m) | MassM(kg) | Depth
D(m) | ThrustD(m) | 2ndMomentExpt. h’’(m) | 2nd moment theory h’’(m) | 0.1 | 0.075 | 0.275 | 0.2 | 0.05 | 0.048 | 0.147 | -0.9167 | | 0.1 | 0.075 | 0.275 | 0.2 | 0.1 | 0.069 | 1.398 | 0.1930 | | 0.1 | 0.075 | 0.275 | 0.2 | 0.15 | 0.085 | 2.575 | 0.1571 | | 0.1 | 0.075 | 0.275 | 0.2 | 0.2 | 0.1 | 3.679 | 0.1467 | | 0.1 | 0.075 | 0.275 | 0.2 | 0.25 | 0.114 | 4.709 | 0.1432 | | 0.1 | 0.075 | 0.275 | 0.2 | 0.3 | 0.128 | 5.389 | 0.1410 | |

Discussion
From the result as we can see, the constant of center of pressure is not stabilize and the error went put the water inside the container also make the unbalance moment to increasing. For the theoretical, we conform that the unbalance went we do the procedure has human error.
The result from experiment center of pressure can make sure that the balance of an object can be stabilizing from this experiment.

Conclusion
The conclusion from this experiment is to realize the center of pressure is important went we want to make the object like ship for stabilize at the sea.

Reference / appendix

Internet : http://en.wikipedia.org/wiki/Center_of_pressure_(fluid_mechanics) http://www.scribd.com/doc/48248012/Center-of-Pressure-on-a-Submerged-Plane-Surface http://www.google.com.my/imgres?q=center+of+pressure+apparatus+experiment&hl=en&biw =1366&bih=624&tbm=isch&tbnid=au130ADEaE90tM:&imgrefurl=http://engineerstoday.blogspot.com/2011/11/experiment-hydraulics-bench-and.html&docid=1HxPHvbyWS81vM&imgurl=http://3.bp.blogspot.com/-AOb-3NWGG9w/TsaLP_dfviI/AAAAAAAABvk/45oOjPICViM/s1600/Hydrostatic_Pressure_Apparatus.jpg&w=575&h=308&ei=iR1zUPi3O8nYrQempIDQCw&zoom=1&iact=hc&vpx=99&vpy=167&dur=3437&hovh=164&hovw=307&tx=191&ty=98&sig=110696072215471710039&page=1&tbnh=99&tbnw=185&start=0&ndsp=20&ved=1t:429,r:0,s:0,i:67