Electron-Nucleus Interaction: Magnitude and Motion

[Winzer]

Homework Statement

1) What is the magnitude of the electric field at a distance of 3.30 ×10−10 m from a thorium nucleus?
2)What is the magnitude of the force on an electron at that distance?
3)Treating the electron classically, that is, as a point object that can move around the nucleus at reasonably slow speeds, what is the period of the electron's motion?
Again treating the electron classically, how fast it it moving?

Homework Equations

$$E=\frac{Kq}{r^2}$$
$$F=\frac{K q_{1} q_{2}}{r^2}$$

The Attempt at a Solution

I can't find anywhere of what the charge of the thorium nucleus is.

 

[rootX]

Homework Statement

1) What is the magnitude of the electric field at a distance of 3.30 ×10−10 m from a thorium nucleus?
2)What is the magnitude of the force on an electron at that distance?
3)Treating the electron classically, that is, as a point object that can move around the nucleus at reasonably slow speeds, what is the period of the electron's motion?
Again treating the electron classically, how fast it it moving?

Homework Equations

$$E=\frac{Kq}{r^2}$$
$$F=\frac{K q_{1} q_{2}}{r^2}$$

The Attempt at a Solution

I can't find anywhere of what the charge of the thorium nucleus is.

not even in peridic table or google?

 

[rootX]

it's here:
http://www.webelements.com/webelements/elements/text/Th/key.html

 

[mgb_phys]

Remember the electron and proton have the same charge, so you just need to know the number of protons in the nucleas = it's atomic number.

 

[Winzer]

not in Columbs,no

 

[rootX]

ohh.. you need to convert it on your own. You wouldn't get it from anywhere.
1 C =6.241506×10E18 electrons or protons

 

[Winzer]

so I got 1.4418e-17 C

 

[rootX]

yep, I also got the same thing