Re: mass increase due to speed

Dear sal:

"sal" <pragmatist@xxxxxxxxxx> wrote in message
news:pan.2006.10.21.03.53.49.698638@xxxxxxxxxxxxx
On Fri, 20 Oct 2006 18:42:04 -0700, N:dlzc D:aol T:com (dlzc)
wrote:
....
Say you were in your ship and measured the mass
of a basketball. You were then accelerated (say to
99% speed of light). If you now measured the
mass of the basketball would you find it 'heavier' or
would it appear the same?

All mass measurements in your frame are with
respect to other masses in your frame. The
basketball in your ship will weigh the same as a
basketball, no matter how fast you are moving.

Now, you observe a basketball in the other ship, on
on the Earth. How do you propose to measure its
mass from your frame?

Let's make this easier. Let's say you are observing
the Moon orbiting the Earth as you fly by at 0.99c.
Will the Earth-Moon system curve your path more
or less than it would at 0.0001c? Will the Moon
suddenly fall into the Earth, will its period suddenly
alter beyond what your gamma accounts for?

You call this making it "easier"??? These are
questions that regularly confuse people who actually
know something of relativity, and you're throwing
them at a newbie here...

The second one is actually a slam dunk, Sal. Think about the
situation...

The Oh My God particle was travelling at such a speed that it
would cross the Milky Way in 1 week proper time (0.999999+c).
Did it cause the Earth and Moon to become black holes, or deform
their orbits in some catastrophic way? Is it plausible that
there was only one of such particles *ever*, or even that this
was the fastest particle to have interacted with the Earth?

Yes you can duck into the math, or you can just look at what you
are expecting of Nature.

As to the first question, it is only slightly more complex...

Realtivistic mass =/= gravitational mass. And gravitational mass
is about the only kind of mass you are going to measure at high
speeds.

David A. Smith


.

Relevant Pages

  • Re: mass increase due to speed
    ... of a basketball. ... All mass measurements in your frame are with ... the Moon orbiting the Earth as you fly by at 0.99c. ... the only kind of mass you are going to measure at high speeds. ...
    (sci.physics.relativity)
  • Re: mass increase due to speed
    ... of a basketball. ... All mass measurements in your frame are with ... the Moon orbiting the Earth as you fly by at 0.99c. ... are going to measure at high speeds. ...
    (sci.physics.relativity)
  • Re: mass increase due to speed
    ... and another identical spaceship moving in a ... impossible to know who's moving and who's stationary. ... But wouldn't measuring the mass of both spaceships tell us ... basketball would you find it 'heavier' or would it appear ...
    (sci.physics.relativity)
  • Re: OT Loose Change 9-11
    ... Gravity is fixed based on the mass of the earth. ... speeds up but reaches a max rate, "terminal velocity", about 120mph. ... other planets objects fall at different rates depending on the mass. ...
    (rec.music.makers.percussion)
  • Re: closer moon?
    ... Orbit period: 365.26 days ... says right here that Mars is going slower than the Earth. ... Why do you talk of "size" when I talk of mass? ... if they have different orbital speeds? ...
    (sci.physics)