- #1
genloz
- 76
- 1
Homework Statement
3. A 15MeV Alpha particle is incident at impact paramter b=0 on a Mg Nucleus, atomic number Z=12 and atomic mass A=24. What is the distance of closest approach?
Homework Equations
None given, but I thought the following might be relevant:
[tex]r_{min}=\frac{Zke^{2}}{KE}[/tex]
[tex]b=\frac{Zke^{2}}{KE} * \sqrt{\frac{1+cos\theta}{1-cos\theta}} [/tex]
The Attempt at a Solution
First I thought that given the above:
[tex]b=r * \sqrt{\frac{1+cos\theta}{1-cos\theta}} [/tex]
[tex]0=r * \sqrt{\frac{1+cos\theta}{1-cos\theta}} [/tex]
[tex]r=0 [/tex]
But then I thought perhaps the distance of closest approach is just the radius of the nucleus:
[tex]r=r_{0}A^{1/3} [/tex]
Now I'm confused about which is appropriate!