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Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do

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On 25/02/2018 12:41 PM, mitchrae3323@gmail.com wrote:
> On Saturday, February 24, 2018 at 5:24:56 PM UTC-8, Sylvia Else wrote:
>> On 25/02/2018 11:06 AM, mitchrae3323@gmail.com wrote:
>>> On Saturday, February 24, 2018 at 3:59:46 PM UTC-8, Sylvia Else wrote:
>>>> On 25/02/2018 10:53 AM, mitchrae3323@gmail.com wrote:
>>>>> Addition of velocities remaining below light speed are clearly understood when moving toward each other at near the speed of light; but what about moving away? That gives subtractions of velocities remaining below the speed light.
>>>>> This is an until now unrecognized flip side of relativity.
>>>>>
>>>>> Mitchell Raemsch
>>>>>
>>>>
>>>> It's already covered by the same formula.
>>>>
>>>> Sylvia.
>>>
>>> It should be.
>>> But where is it used? There is a difference between
>>> toward and away...
>>>
>>> Mitchell Raemsch
>>>
>>
>> It's used where the situation demands. Just change the sign of one of
>> the velocities.
>>
>> Sylvia.
> 
> How do you define the situation?
> That is not how it works.
> How do you define the velocities as positive
> when they are subtracting?
> Why would it?
> 
> Mitchell Raemsch
> 

The sign of the velocity is a convention. If the velocities are in the 
same direction then they're both deemed positive, and the (inevitably 
positive) result is for a velocity in the same direction.

If the two velocities are in opposite directions, then you choose one of 
them to be deemed positive, and the other negative. If the result is 
positive, then the resulting velocity is in the direction of the 
velocity deemed positive. Otherwise it's in the opposite direction.

Sylvia.

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More Relativity; Subtraction of velocities keeping below light speed; as Additions do mitchrae3323@gmail.com - 2018-02-24 15:53 -0800
  Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do Sylvia Else <sylvia@not.at.this.address> - 2018-02-25 10:59 +1100
    Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do mitchrae3323@gmail.com - 2018-02-24 16:06 -0800
      Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do Sylvia Else <sylvia@not.at.this.address> - 2018-02-25 12:24 +1100
        Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do mitchrae3323@gmail.com - 2018-02-24 17:41 -0800
          Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do Sylvia Else <sylvia@not.at.this.address> - 2018-02-25 15:16 +1100
            Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do mitchrae3323@gmail.com - 2018-02-24 21:15 -0800
              Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do Sylvia Else <sylvia@not.at.this.address> - 2018-02-25 16:50 +1100
                Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do mitchrae3323@gmail.com - 2018-02-24 21:58 -0800
                Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do Sylvia Else <sylvia@not.at.this.address> - 2018-02-25 19:18 +1100
                Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do mitchrae3323@gmail.com - 2018-02-25 15:02 -0800
              Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do pnalsing@gmail.com - 2018-02-24 22:08 -0800
  Re: More Relativity; Subtraction of velocities keeping below light speed; as Additions do David Waite <waitedavid1618@yahoo.com> - 2018-02-24 22:06 -0800

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