OT: Speed of light [was Re: Why not a Python compiler?]

[Robert Bossy]

Jeff Schwab wrote:
> Erik Max Francis wrote:
>   
>> Jeff Schwab wrote:
>>
>>     
>>> Erik Max Francis wrote:
>>>       
>>>> Robert Bossy wrote:
>>>>         
>>>>> I'm pretty sure we can still hear educated people say that free fall 
>>>>> speed depends on the weight of the object without realizing it's a 
>>>>> double mistake.
>>>>>           
>>>> Well, you have to qualify it better than this, because what you've 
>>>> stated in actually correct ... in a viscous fluid.
>>>>         
>>> By definition, that's not free fall.
>>>       
>> In a technical physics context.  But he's talking about posing the 
>> question to generally educated people, not physicists (since physicists 
>> wouldn't make that error).  In popular parlance, "free fall" just means 
>> falling freely without restraint (hence "free fall rides," "free 
>> falling," etc.).  And in that context, in the Earth's atmosphere, you 
>> _will_ reach a terminal speed that is dependent on your mass (among 
>> other things).
>>
>> So you made precisely my point:  The average person would not follow 
>> that the question was being asked was about an abstract (for people 
>> stuck on the surface of the Earth) physics principle, but rather would 
>> understand the question to be in a context where the supposedly-wrong 
>> statement is _actually true_.
>>     
>
> So what's the "double mistake?"  My understanding was (1) the misuse 
> (ok, vernacular use) of the term "free fall," and (2) the association of 
> weight with free-fall velocity ("If I tie an elephant's tail to a 
> mouse's, and drop them both into free fall, will the mouse slow the 
> elephant down?")
>   
In my mind, the second mistake was the confusion between weight and mass.

Cheers
RB