Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

?
Lv 5
? asked in Science & MathematicsPhysics · 1 decade ago

Time Dilation and relative velocity, 2 girls, 3 atomic clocks?

Right, Time dilation due to velocity has been experimentally demonstrated when a airline took an atomic clock up traveled at speed and then came back down again comparing the atomic clock with one on the ground it was measurably behind the control clock.

So... Girl 1 takes her atomic clock on one plane and girl 2 takes hers on another and the control clock stays on the ground. The two planes travel away from each other at the same velocity so to the control clock both plane-bound clocks should fall behind by the same amount but to girl 1 who accepts her position as reference zero girl 2 is traveling at a greater velocity and to girl 2 who accepts her position as reference zero girl 1 is traveling at a greater velocity. Both girls should expect that when they meet to compare clocks that the other girls is behind by an amount.

when they do meet how can they both see the others clock as being behind and will a ground observer see both as being equally behind the control.

Informed answers only please I will call you an idiot if you fail to understand the question.

Update:

Billruss...

I think you misunderstood, Velocity affects time dilation not tates of change and there is no such thing as a correct frame of references all frames in my example are equally valid

Ronoh...

Why?

Update 2:

Lola F

Why then if you took girl a and the earth clock not sych up when girl a returns to earth? since relative to each other both of thier reference frames would have undergone the same inertial reference frame changes.

4 Answers

Relevance
  • Lola F
    Lv 7
    1 decade ago
    Favorite Answer

    Time dilation is not the only effect of Relativity. Failure of Simultaneity is another, and the one that everyone always forgets about.

    While they are traveling at constant speeds, each girl observes the other's clock to run slow, just as each girl observes the Earth's clock to run slow. However, when they turn back towards the Earth, each changes her reference frame to a new frame with a different definition of which events are happening "now."

    It's the same as the resolution of the original twin paradox. Just before the twin turns around, she's in a frame in which her clock reading 1 hour is simultaneous with (for instance) the Earth's clock reading only 1 minute. After she turns around, she's in a new reference frame where her 1-hour clock is simultaneous with the Earth's clock reading many days. Aside from that turnaround, she always observes Earth's clocks running slow, and yet when she returns Earth's clock is far ahead of hers: because of the shift in simultaneity when she accelerates.

    The same is true in your example. Each girl observes the other's clock to run slow, except when she jumps reference frames when she turns around. At that point, she shifts into a reference frame in which her twin's clock reads much farther ahead than it did just before the turnaround--- exactly enough so that, when they return to Earth, even though she observes the other's clock to run slow all the time (except at the turnaround), their clocks will read the same amount when they meet again.

  • 1 decade ago

    This can be understood better if you consider two girls traveling via spaceships in opposite directions. The travel a round trip, and after 2 years, return home, with both aging only 1 year. (case 1)

    If you take one of the girls as reference, then you could say the other picked up 2 years in time while the reference didn't. (case 2) But this is not true to the facts, as they can compare their ages.

    The difference between the two cases is acceleration, both girls underwent extended accelerations, while the earth didn't. That means the earth is the correct reference (case 1) since, while speed is relative, acceleration is not.

    Apply this to your example...

    .

  • ?
    Lv 4
    5 years ago

    CM Punk Ezekiel Jackson Hart Dynasty Sarita Abyss Christian Best promo needed to be The Miz outsmarting Shawn Michaels WQ1- With the entire dream suits how can Morrison no longer be foremost eventer? Morrison vs Shamus Morrison vs Jericho Morrison vs Edge Morrison vs Orton WQ two- Draft has made Raw into the satisfactory company WWE has to present, Smackdown will probably be ok with Jack Swagger, Christian, Undertaker and CM Punk along with his Straight Edge Society main the best way. i'm unhappy Batista is leaving WWE despite the fact that, certainly not noticed that coming through a mile WQ3- Ted Dibiase staying on Raw used to be gigantic dissatisfied, with Jericho, Edge,Shamus as the highest heels, he is most often will keep as moderate card wrestler for now. no longer definite what plans WWE inventive writers has in retailer for him ):

  • Anonymous
    1 decade ago

    Ok, this can best be demonstrated when the two girls go in the opposite direction and return back after one year

Still have questions? Get your answers by asking now.