Estimating Nucleons in a 85 kg person.

[titan81]

Homework Statement

Estimate the number of nucleons found in the body of a 85 kg person.

Homework Equations

The Attempt at a Solution

This all of the information they give for this problem so I am not sure what equations or what other numbers to use.

 

[berkeman]

Homework Statement

Estimate the number of nucleons found in the body of a 85 kg person.

Homework Equations

The Attempt at a Solution

This all of the information they give for this problem so I am not sure what equations or what other numbers to use.

It would seem that you need the average density of a human. What Google terms do you think you could use to find some estimates of that?

 

[Borek]

Density? I would rather start assuming in most elements involved ratio of neutrons:protons is the same. and there is no mass deficit. Then 85 kg is just a dead giveaway...

 

[gneill]

Homework Statement

Estimate the number of nucleons found in the body of a 85 kg person.

Homework Equations

The Attempt at a Solution

This all of the information they give for this problem so I am not sure what equations or what other numbers to use.

The mass of a neutron is pretty close to that of the proton, so for the sake of estimation you might consider the entire body to be made up of neutrons, and discount the contribution of electrons to the overall mass (their numbers are commensurate with the number of protons in order to render the overall body neutral).

To get a more accurate estimate you'd need to break down the elemental composition of the body and sum the separate contributions of protons and neutrons from each.

http://web2.airmail.net/uthman/elements_of_body.html"

It would be a lengthy task to do this for every element involved!

You'll have to decide how accurate an estimate is being asked for.

 

[p21bass]

The mass of a neutron is the same no matter what element you're talking about. The composition of the human body is irrelevant to this problem. All you need is the mass of the object (given as 85kg) and the mass of a nucleon.

 

[gneill]

The mass of a neutron is the same no matter what element you're talking about. The composition of the human body is irrelevant to this problem. All you need is the mass of the object (given as 85kg) and the mass of a nucleon.

Nucleons include both protons and neutrons, and their masses are not exactly equal. For a more accurate estimate you'd need to know the numbers of each involved, and each element has different numbers of each.

It could be that the OP's requirements do not require this sort of finesse.

 

[Borek]

The mass of a neutron is the same no matter what element you're talking about.

Yes and no. Because of the binding energy apparent mass of nucleons is different for different nuclei.