Identifying Different Radioactive Balls Easily

[dark_vader93]

There are 2 radioactive balls, which have the same radius and the same weight. They are covered with absorbing layer. They are made of diffrent materials, with other half-life. What is the easiest way to recognise which is which?
I had searched for the answer for a longer time and could not find out. Please for help.

 

[daveb]

What do you mean by an absorbing layer? Do you mean the layer absorbs all of the radiated particles and energy from the radioactivity?

 

[sophiecentaur]

You could, in principle, measure a change in densities somehow? ( Hint.)

 

[256bits]

If you had the 2 balls with different levels of radiactivity immersed ( frak - I had to look up how to spell that word ) in separate baths of water in inslolated containers each with thermal instrumentation, could you devise a way to tell them apart?

 

[dark_vader93]

thank you very much. that's a great idea to measure their densities or temperatures. i think, that one with density is the easiest one. you put them in water and the ball which has longer half-life would move down faster.

 

[dark_vader93]

What do you mean by an absorbing layer? Do you mean the layer absorbs all of the radiated particles and energy from the radioactivity?

yes.

 

[sophiecentaur]

thank you very much. that's a great idea to measure their densities or temperatures. i think, that one with density is the easiest one. you put them in water and the ball which has longer half-life would move down faster.

But remember, the problem, I think, demands that all products of the reaction stay within the ball. So how would you measures density change and 'which' densities would change?

 

[Matterwave]

I vote for spinning the ball. If there is a layer (like skin) absorbing the radiated particles, then the moment of inertia of the balls should change at different rates.

 

[sophiecentaur]

I vote for spinning the ball. If there is a layer (like skin) absorbing the radiated particles, then the moment of inertia of the balls should change at different rates.

Go for it my son.

 

[csmcmillion]

My g/f says I have two radioactive balls. ;-)

 

[sophiecentaur]

How fast are they decaying?

 

[csmcmillion]

> How fast are they decaying?

Pretty fast these days. The interesting thing is that the decay rate is highly non-linear lately. I observed no decay in the first 20 years, a linear decay in the next ten years, somewhat of a geometric rate in years 30- 40, but since year 40 the rate appears to be exponential.

I have no rational explanation for my observations.

 

[sophiecentaur]

Use it or lose it my friend. No reason for things to fizzle out before the age of ninety!