Question
What is the radius of an alpha particle?
$1.9 \textrm{ fm}$
Solution Video

OpenStax College Physics Solution, Chapter 31, Problem 7 (Problems & Exercises) (0:33)

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Video Transcript

This is College Physics Answers with Shaun Dychko. The radius of a nuclide is given by this equation— <i>r naught</i> times the mass number to the power of one-third— this is equation [31.7]. <i>r naught</i> is 1.2 fermis, or femtometers, and for a <i>α</i>-particle, the mass number is 4 because there are 4 nucleons in the helium nuclide and raise that to the power of one-third and you get 1.9 femtometers.