[Damiano0707]

Hi
My book says that when you weigh an object with a way different density related to the standard mass, you can have an error. This is because of the different buoyant forces on the weighed object and the standard mass. Then it puts this formula to calculate the right mass of the weighed object

W=W_1+W_1(d_air/d_object-d_air/d_mass)

Where W is the right mass
W_1 is the weighed mass
d_air is the air's density
d_object is the object's density
d_mass is the standard mass' density

What is the derivation of this formula?
Thaks to all

[Borek]

Should be rather trivial physics, I would start by calculating the difference between real mass of an object of density d and its mass weighed in the air.