Re: space-time + matter/energy OR space-time-matter


"Michael Hell" <mobydikc@xxxxxxxxx> wrote in message
news:1165394744.598134.6790@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Dirk Van de moortel wrote:

[snip]
What is the KE of the object at 0 seconds?

Here again is what is known:

a ball is 100 m above the earth when the clock says 0 seconds
the mass of the earth is 5.9742 × 10^24 kg
the mass of the ball is 50 kg
and at 1 second, the ball is 50 m above the earth
only the altitude has changed, the latitude and longitude of the ball
are fixed

My answer is:

the ball traveled 50 m in 1 second, so its average velocity is 50m/s
the ball would accelerate 9.8 m/s during that one second due to gravity
so the ball's initial velocity must be 40.2 m/s
the KE = 1/2 * 50 kg * 40.2 m/s

1005 kg*(m/s)^2

If that's the wrong answer, I suppose it is because the instantaneous
velocity is not 50 m/s at 1 second.

If that's the wrong number, what's the right one?

Added to:
http://users.telenet.be/vdmoortel/dirk/Physics/Fumbles/GreaterPhysicist.html
I hope that no-one will be naive enough to spell it out for you ;-)


You hope that I can remain in the dark so that you can feel good about
how much better you are than I.

You are a bad person.

Not really.
That's just an impression some arrogant crackpots tend to have :-)

Dirk Vdm


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