[lynxk]

Hi all!

I've no idea if this is the right place, but I'm having a problem solving this..(I'm translating this into English so I hope itll be clear) :

Assume that the mass of an atom is concentrated in its nucleus, in an orb formation, with a radius r,
that is equal to 1.5 x 10^-5.  (1 picometer = 10^-2 m )

1. If a carbon's mass is 2.0 x 10^-23 gr, what would be the density of its nucleus? The volume of the orb is 4/3 π r.

2. What would be the earth's radius, If its density equals to that of the carbon's atom? (The average radius of the earth is
6.4 x 10^3 km, and ts average density is 5.5 gr/cm^-3)


I hope its clear enough. Please move it to the right section if its not, Im kinda desperate.
And please be kind to show me the entire calculation.

Thanks you so much in advanced for your assistance! ^^

[kizzler85]

density = mass/volume

[lynxk]

Right. I know that |:

What I dont know is how to calculate this whole thing. 

[opti384]

You have everything given to find the denstiy.

In the first question you have the mass and you can find the volume since you know the radius.

[Borek]

Note - pm is not 10^-2. Beware of the units, you are treating them way too freely IMHO.