Formula of object immersed in water

In summary, the equation for finding the y-coordinate of the centroid (yc) is defined as 1/A multiplied by the integral of y with respect to A. Therefore, at 3-20, the equation for the moment of inertia (P0) multiplied by the integral of y with respect to A will result in P0 times Ay, not P0 times yc2.
  • #1
werson tan
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1

Homework Statement


why the y ſ P dA will equal to P yc A ? why not P (yc^2) A ? since yc = ſ y dA / A

Homework Equations

The Attempt at a Solution

 

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  • #2
It comes from the definition of yc at 3-18.
 
  • #3
haruspex said:
It comes from the definition of yc at 3-18.
according to 3-18 , i would get P (yc^2) A instead of P (yc) A ... am i correct ?
 
  • #4
werson tan said:
according to 3-18 , i would get P (yc^2) A instead of P (yc) A ... am i correct ?
No.
3-18 defines ##y_c=\frac 1A\int_AydA##. So at 3-20, ##P_0\int_AydA=P_0Ay_c##.
How do you get yc2 terms?
 
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FAQ: Formula of object immersed in water

1. What is the formula for calculating the volume of an object immersed in water?

The formula for calculating the volume of an object immersed in water is: V = Vw - V0, where V is the volume of the object, Vw is the volume of the water displaced by the object, and V0 is the volume of the object above the water's surface.

2. How does the density of an object affect its immersion in water?

The density of an object plays a crucial role in determining how much of the object will be submerged in water. Objects with a higher density than water will sink, while objects with a lower density will float. The amount of water displaced by the object is equal to its volume, and this volume will determine how much of the object is submerged.

3. Can the formula for immersion in water be applied to irregularly shaped objects?

Yes, the formula for immersion in water can be applied to irregularly shaped objects as long as the volume of the object can be accurately measured. The volume of the object can be calculated by measuring the amount of water it displaces when fully immersed in a container of water.

4. How does the temperature of the water affect the immersion of an object?

The temperature of the water does not have a significant impact on the immersion of an object. However, warmer water is less dense than colder water, so an object will displace more water in warmer water compared to colder water. This means that the object will appear to be more buoyant in warmer water, but the volume of the object remains the same.

5. How does the shape of an object affect its immersion in water?

The shape of an object does not directly affect its immersion in water. However, the shape of an object can influence its density, which in turn affects its immersion. For example, an object with a larger surface area will displace more water and appear more buoyant than an object with a smaller surface area, even if they have the same volume and density.

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