Calculating density Archimedes principle

[noname1]

I have to calculate the density of these 3 objects and these are the values i obtained but now i am confused how i can calculate the density of them.

I know that in chemistry density is mass / volume but in this case i am not sure, can anyone tell me the formula?

thanks in advance

 

[Cilabitaon]

If you know the volume of the sphere then you should be able to use \rho = \frac{m}{V}

If you don't have the volume but have the radius and length of the cylinder then you can work out volume.

If you don't have the radii of the cylinders or their length then get out your ruler =]

 

[noname1]

If you know the volume of the sphere then you should be able to use \rho = \frac{m}{V}

If you don't have the volume but have the radius and length of the cylinder then you can work out volume.

If you don't have the radii of the cylinders or their length then get out your ruler =]

we don't have any measurements of the objects, that's why i find it complicated

 

[ideasrule]

I see that you've already calculated the force of buoyancy on the objects. Fb=rho*g*V where rho is the density of water, so you can easily calculate the objects' volume.