Question

Suppose the range for5.0 MeVα ray is known to be2.0mmin a certain material. Does this mean that every5.0 MeVα a ray that strikes this material travels 2.0mm , or does the range have an average value with some statistical fluctuations in the distances traveled? Explain.

Short answer

No this does not means that all the 5.0 MeVα particle will travels 2.0mm .

Step-by-step solution

Definition of statistical fluctuations

Quantity variations that result from numerous identical random processes are known as statistical fluctuations. They are necessary and inescapable. It is demonstrable that the number of identical processes increases as the square root of the relative fluctuations.

Step 2: 5.0 MeVα ray travels 2.0 mm in medium 

No this does not means that all the 5.0 MeVα particle will travels 2.0 mm in that medium. This is purely probabilistic. That is, when α particles travels through the medium, it collides with the particle of the medium and then get absorbed by it or decayed in it. Now this is purely probabilistic, when one α particle will collide with other particle. So this is some average value with some statistical fluctuation.

Therefore, no this does not means that all the 5.0 MeVα particle will travels 2.0 mm.