The Open Door Web Site
HOME PAGE BIOLOGY CHEMISTRY PHYSICS ELECTRONICS HISTORY HISTORY of SCI & TECH MATH STUDIES LEARN FRENCH STUDY GUIDE PHOTO GALLERY
ATOMIC and NUCLEAR ELECTRICITY and MAGNETISM MEASUREMENTS MECHANICS OPTICS PRACTICAL WORK QUESTIONS RELATIVITY THERMAL PHYSICS WAVES
PRACTICAL WORK
Google
Custom Search
Atomic and Nuclear Physics
 
Comparing Radio-active Decay with other Random processes
See, Radio-active decay
 
Experiments show that radio-active decay is a random process.
There appears to be no way of predicting when a particular nucleus will give out its radiation.
However, useful predictions can be made if we have large numbers of unstable nuclei.
This is, in practice, always the case.
Consider for example the radio-active substance radium D.
This substance (which is an isotope of lead) has mass number 210.
This means that 1 mol of it has a mass of about 210g.
Therefore, even if we only had 1milli-gram of radium D, we would have about
NA(110-3)/210
where NA is Avogadro's number.
This gives about 2.871018nuclei... quite a lot!
 
In this experiment, rather than observing the behaviour of a radio-active substance we will observe another process which exhibits random behaviour.
Try to get hold of 100 dice (assumed to be identical).
Throw the dice onto a horizontal surface and see how many have landed with, for example, the "6" side up.
Each die represents a nucleus of a radio-active substance.
Consider those which land with the "6" side up to represent nuclei which have decayed and become stable in some (arbitrary) period of time.
How many would you expect to have the "6" upwards?
Separate these "decayed nuclei" from the others.
 Collect the "undecayed nuclei" and throw again, repeating the selection process... and again... and again etc.
Stop when you have about 10 left.
Then repeat the whole process as many times as you can making sure that you have the same number of throws in each set of results.
Record the number of dice N removed after each throw.
 
Plot a graph of N (vertical) against "number of throw".
This graph can be considered to be equivalent (in some ways) to the radio-active decay curve.
What is the half life of your radio-active dice dice?
 
SITE MAP
WHAT'S NEW
ABOUT
PRIVACY
COPYRIGHT
SPONSORSHIP
DONATIONS
ADVERTISING
 

© The Open Door Team
2016
Any questions or
problems regarding
this site should be
addressed to
the webmaster

David Hoult 2017

Hosted By
Web Hosting by HostCentric

 
SiteLock
 
 
Practicals Index Page