Calculate Elsie's Statue Density: 6100N, 302.4kg Mass

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To calculate the density of Elsie's statue, the relevant equations involve the buoyant force and the mass of the statue. The density of water is approximately 1000 kg/m^3, and the volume of the statue can be derived from its mass and density. Using the force of 6100 N and the mass of 302.4 kg, the calculations show that the density of the statue is approximately 20.13 kg/m^3. This result differs from the expected answer of 327 kg/m^3, suggesting potential errors in the provided values or calculations. Accurate unit conversion and careful verification of inputs are crucial for correct results.
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A wooden statue of Elsie the cow is held under water in a swimming pool with a force 6100 N. If Elsie's mass is 302.4 kg, what is the density of the statue?

This was off my last test, I know the set up from the problem was something like:
density(water)*g*V=density(statue)*g*V+external force
and V=m(statue)/density(statue)
but I must be messing up the density of the water, and I do not know how to find the volume of the statue. I got 105 which was a choice on the test, but it was incorrect and the answer is 327. I must be plugging in the wrong numbers unless the test was wrong. Please let me if you see where the 327 came from. Thanks. Maybe this is even the wrong equation I am using, but I thought this was correct.
 
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fozziejr2 said:
density(water)*g*V=density(statue)*g*V+external force
and V=m(statue)/density(statue)
Nothing wrong with that.
but I must be messing up the density of the water, and I do not know how to find the volume of the statue.
The density of water is about 1000 kg/m^3. Don't neglect to take full advantage of the given information: the mass of the statue. Using this information, everything on the right side of your first equation is known; you should be able to solve for V, and then the density.
 


To calculate Elsie's statue density, we can use the formula: density = mass/volume. In this problem, we are given the force of 6100N and the mass of 302.4kg. We can also assume that the external force mentioned in the problem is the buoyant force of the water acting on the statue. Therefore, we can set up the equation as follows:
density(water)*g*V = density(statue)*g*V + external force
To find the volume of the statue, we can rearrange the equation to solve for V:
V = mass(statue)/density(statue)
Plugging in the given values, we get:
V = 302.4kg/density(statue)
Now, we need to find the density of water. The density of water is approximately 1000 kg/m^3, or 1 g/cm^3. Plugging this value into the equation, we get:
V = 302.4kg/1000kg/m^3
Simplifying, we get:
V = 0.3024m^3
Therefore, the volume of the statue is 0.3024m^3.
Now, we can plug this value back into the original equation to solve for density(statue):
density(water)*g*0.3024m^3 = density(statue)*g*0.3024m^3 + 6100N
Substituting the density of water and rearranging the equation, we get:
density(statue) = (6100N - 0.3024m^3*1000kg/m^3*g)/0.3024m^3*g
Simplifying, we get:
density(statue) = 20.13 kg/m^3
Therefore, the density of Elsie's statue is approximately 20.13 kg/m^3. This is different from the given answer of 327 kg/m^3, which could be due to rounding errors or incorrect values given in the problem. It is important to double check the given values and units to ensure accurate calculations.
 
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