Archimedes' Problem: Iron Body Submerged in Water

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The discussion revolves around calculating the buoyant force and apparent weight of an iron body submerged in water. The initial calculation of the iron body’s volume as 0.000633 m³ is questioned, with suggestions to use the formula for density to find the correct volume. The correct volume is determined to be approximately 1.699 x 10^-6 m³, leading to a revised buoyant force calculation. The apparent weight of the iron in water is recalculated to be approximately 0.1133 N. The thread emphasizes the importance of using accurate density definitions in these calculations.
germangb
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i have the following problem:
-an iron (7800kg/m3) body is submerged into in water (density = 1000kg/m3)
his weight in the air is 0,13N.

what i did is:

E=dVg (Push force, density of the liquid, volume of the body sumerged and gravity, respectively)

then:
the volume of the iron body is 0,000633m3, then:

E = 1000*0,000633g = 1,60

so, the the apparent weight is 0,13-1,60= -1,47N
______________________________
did I do it right?
 
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how did you get volume of iron body as that? and how do you get 1000*0.000633*g = 1.60??

find volume correctly first. see that actual weight is 0.13N, therefore m = 0.13/g Kg. use density to find volume.

tell us what you get.
 
germangb said:
i have the following problem:
-an iron (7800kg/m3) body is submerged into in water (density = 1000kg/m3)
his weight in the air is 0,13N.

what i did is:

E=dVg (Push force, density of the liquid, volume of the body sumerged and gravity, respectively)

then:
the volume of the iron body is 0,000633m3, then:

E = 1000*0,000633g = 1,60

so, the the apparent weight is 0,13-1,60= -1,47N
______________________________
did I do it right?

Use basic definition for density.
Volume(iron) = .13/(g*density)=1.699x10^-6 m3

Weight of iron in water = (weight in air) - dVg = .1133N

I'm open for correction.
 
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