Re: Physics Question

From	Sergio <invalid@invalid.com>
Newsgroups	sci.physics
Subject	Re: Physics Question
Date	2016-07-10 11:15 -0500
Organization	Aioe.org NNTP Server
Message-ID	<nltsa6$hfl$3@gioia.aioe.org> (permalink)
References	(1 earlier) <nlnj6p$4h7$1@dont-email.me> <nlofhc$lat$2@pcls7.std.com> <nlofq5$1hc6$1@gioia.aioe.org> <57801761$0$43792$c3e8da3$5e5e430d@news.astraweb.com> <nlp64h$isi$1@gioia.aioe.org>

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On 7/8/2016 4:32 PM, Odd Bodkin wrote:
> On 7/8/2016 4:12 PM, benj wrote:
>> On 7/8/2016 11:11 AM, Odd Bodkin wrote:
>>> On 7/8/2016 10:06 AM, Michael Moroney wrote:
>>>> Poutnik <poutnik4nntp@gmail.com> writes:
>>>>
>>>>> Dne 07/07/2016 v 15:28 Sergio napsal(a):
>>>>>> 1. A sample of radioactive nuclei of a certain element can decay
>>>>>> only by
>>>>>> gamma-emission and beta-emission. If the half-life for
>>>>>> gamma-emission is
>>>>>> 24 minutes and that for beta-emission is 36 minutes, the half-life
>>>>>> for
>>>>>> the sample is
>>>>>>
>>>>>> (A) 30 minutes
>>>>>> (B) 24 minutes
>>>>>> (C) 20.8 minutes
>>>>>> (D) 14.4 minutes
>>>>>> (E) 6 minutes
>>>>>>
>>>>> F: Incomplete scenario definition without probabilities.
>>>>
>>>> The half-lives give the probabilities.
>>>
>>> Right, and the answer is D, I believe.
>>>
>>>>
>>>>> Aside of that, gamma emission itself is not radioactive decay,
>>>>> it is releasing energy of excited kernel.
>>>>
>>>> Some isotopes have "meta" (excited) states that can give off
>>>> a gamma to become the ground state.  Some of these isomers
>>>> can also decay radioactively to something else by giving off an
>>>> alpha or beta.  And sometimes the ground state can't decay
>>>> the same way the isomer can.
>>
>> As usual, amateur Boinker goes for the simplest answer which is wrong.
>
> Then what's the answer and why?
>
>>
>> MM and Pouter have the correct information.
>
> Poutnik said there was probability information missing, and Michael
> rightly pointed out that the probability information is expressed in the
> half-lives. Poutnik then agreed. So what information do you think is
> missing?
>
>>
>> But then shooting off your mouth when you have insufficient information
>> is what Boinker calls science.
>>
>
>

found the orgional source, the answer is D, this came from example 
physics GRE question,
I think they are just using what I call the combing of failure rate 
equation

Thread

Physics Question Sergio <invalid@invalid.com> - 2016-07-07 08:28 -0500
  Re: Physics Question Poutnik <poutnik4nntp@gmail.com> - 2016-07-08 09:02 +0200
    Re: Physics Question Sergio <invalid@invalid.com> - 2016-07-08 09:19 -0500
    Re: Physics Question moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-08 15:06 +0000
      Re: Physics Question Odd Bodkin <bodkinodd@gmail.com> - 2016-07-08 10:11 -0500
        Re: Physics Question benj <benj@nobody.net> - 2016-07-08 17:12 -0400
          Re: Physics Question Odd Bodkin <bodkinodd@gmail.com> - 2016-07-08 16:32 -0500
            Re: Physics Question Sergio <invalid@invalid.com> - 2016-07-10 11:15 -0500
              Re: Physics Question Fabian Russell <fb@zen.info> - 2016-07-10 19:25 +0000
                Re: Physics Question Odd Bodkin <bodkinodd@gmail.com> - 2016-07-10 15:43 -0500
                Re: Physics Question Fabian Russell <fb@zen.info> - 2016-07-10 21:52 +0000
                Re: Physics Question Odd Bodkin <bodkinodd@gmail.com> - 2016-07-11 07:50 -0500
                Re: Physics Question Poutnik <poutnik4nntp@gmail.com> - 2016-07-11 17:04 +0200
                Re: Physics Question moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-11 01:20 +0000
      Re: Physics Question Poutnik <poutnik4nntp@gmail.com> - 2016-07-08 19:01 +0200
        Re: Physics Question Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-09 21:28 +0200
          Re: Physics Question moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-10 02:18 +0000
    Re: Physics Question Fabian Russell <fb@zen.info> - 2016-07-09 17:11 +0000

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