Trying to find volume given Newtons/ archimedes principle

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bc1170
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Homework Statement



A paperweight, when weighed in air, has a weight of W = 6.6 N. When completely immersed in water, however, it has a weight of Win water = 4.0 N. Find the volume of the paperweight.


Homework Equations



Fb = Wfluid


The Attempt at a Solution



I can find density using density of object/density of water=weight of object/initial weight-immersed weight

but can not seem to find out how to find volume... I am stuck
 
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I am not sure.. I know that Newtons are kg/s^2 I just don't know how it relates in any way to volume
 
Newton's are kg*m/s^2. They are a unit of force. They have the same units as m*a (in F=ma). Volume relates to mass through density. Mass relates to force through weight equals mg (m is mass and g is the acceleration of gravity). You might want to review some of these topics.
 
The nitty gritty of it is as follows.
the Difference of the weight in the air, and the weight in the water equals weight of the object
Therefore, we use the following steps to find the volume of the object.

Step 1)
6.6 N -4.0 N = 2.6 N <--weight of water displaced

Step 2)
Divide by gravity to get mass of object
2.6 N / 9.81 m/s^2 = .265kg <-- mass of object

Step 3)
Take that and divide by the density of water
.265kg / 1000kg/m^3 = 2.65E-4 m^3 <--equals the volume of the object