A Levels Physics

A class of students used dice to simulate radioactive decay. After each throw, those dice showing
a '6' were removed. The graph shows the results.
100
number of
80
dice remaining
60-
40-
20
4
6
8
10
number of throws of the dice
What could the scatter of points about the best-fit curve represent for actual radioactive decay?
A background count not being taken into account
B more than one type of radiation being present
c the random nature of radioactive decay
D the spontaneous nature of radioactive decay


Choice C is correct because:

The scatter of points about the best-fit curve does represent the random nature of radioactive decay.

The random nature of actual radioactive decay is represented by the fact that the radioactive decay graph has fluctuations in the count rate. This phenomenon is exactly represented by the scatter (fluctuation) of points about the best-fit curve 

Choice A is incorrect because:

The scatter of points about the best-fit curve does not represent the background count not being taken into account.

The background count not being taken into account of actual radioactive decay is represented by the fact that the radioactive decay graph becomes constant (zero gradient) at a certain count rate which is not 0 (the graph does not intersect the x-axis). This is not represented by the die experiment & graph shown in the question.

Choice B is incorrect because:

The scatter of points about the best-fit curve does not represent more than one type of radiation being present.

In actual radioactive decay, more than one type of radiation being present is represented by the fact that the radioactive decay graph has certain points which are large anomalies. This is not represented by the die experiment & graph shown in the question.

Choice D is incorrect because:

The scatter of points about the best-fit curve does not represent the spontaneous nature of radioactive decay.

The spontaneous nature of actual radioactive decay is represented by the fact that the radioactive decay graph has the same shape even at different temperatures, pressures etc. This is not represented by the die experiment & graph shown in the question.

Particle and Nuclear Physics | 2012 - O/N - 9702/11 | Q38