<p>can anyone explain me a few things with modern physics? what will we actually need to know for the test? and what is the deal with stopping potential?? it makes no sense to me</p>
<ol>
<li>In alpha decay, the mass number drops by 4 and the atomic number drops by 2.<br></li>
<li>In beta- decay, the mass number remains the same and the atomic number increases by 1 (A neutron turns into a proton)</li>
</ol>