Solve Problem with Density: Find Object's Density

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To find the density of an object weighing 20 grams in air and 3.5 grams in a liquid with a density of 1.7 g/cm³, the correct approach involves calculating the volume displaced. The volume is determined by the difference in weight, leading to a calculation of approximately 9.7 cm³. The density is then calculated by dividing the object's weight in the liquid by the volume, resulting in a density of 0.36 g/cm³. However, it's important to clarify that mass, not weight, should be used in density calculations. The discussion emphasizes the distinction between mass and weight in solving density problems.
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Homework Statement


if an object weighs 20 grams in air but 3.5 grams in a liquid of density 1.7g/c,^3
What is the density of the object?


Homework Equations


density=m/v


The Attempt at a Solution


v=20-3.5/1.7
=9.7
then, density would be;
d=3.5/9.7
=0.36
Is that correct?
 
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yoleven said:

The Attempt at a Solution


v=20-3.5/1.7
=9.7
This is good. (Units = cm^3, I presume.)
then, density would be;
d=3.5/9.7
=0.36
Careful. What's the mass of the object?
 
thanks, as usual!
 
mass is a measure of matter not weight!
 

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