Physics

posted by .

In its own frame the average pi meson lives 2.60 x 10^-8s. Suppose it moves at 0.985c relative to the Earth. According to us, on Earth, what is a pi meson's average lifetime? (b) according to us, what is the pi meson;s average travel distance before decaying? (c) If time dilation did not occur what would we see as the pi meson's average travel distance before decaying?

  • Physics -

    The π meson’s lifetime in its own frame is the proper time
    interval, tₒ =2.6•10^−8 s. An earthbound observer measures a longer dilated time interval t . If β =0. 985,
    t = tₒ/sqrt(1-β²) = 2.6•10^−8 /sqrt(1-0.985²) =1.5•10^-7 s.
    The distance the π meson travels in the earthbound observer’s reference frame is the π-meson’s velocity multiplied by the time interval measured by the earthbound observer. (Note that this is the relative velocity)
    d = v•t =0.985•c•1.598510^-7 = 0.985•3•10^8•1.5•10^-7 = 44.5 m,
    Without time dilation, the distance traveled would just be the proper lifetime multiplied by the meson’s velocity:
    s = 0.985• c•2.6•10^−8 =7.68 m.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    The earth moves around the sun in a nearly circular orbit of radius 1.50*10^11m. During the three summer months (an elapsed time of 7.89*10^6s), the earth moves one-fourth of the distance around the sun. (a)what is the average speed …
  2. physics

    A proper lifetime of a certain particle is 100.0ns. a) How long does it live in the lab frame if it moves at V=0.960c?
  3. physics

    A proper lifetime of a certain particle is 100.0ns. a) How long does it live in the lab frame if it moves at V=0.960c?
  4. Physics

    On earth, a certain type of bacteria doubles in number every 24 hours. Two cultures of these bacteria are prepared, each consisting initially of one bacterium. One culture is left on earth and the other is put on a rocket travelling …
  5. Physics

    According to Anna, on Earth, Bob is on a spaceship moving at 0.8c towards Earth, and Carl, a little farther out, is on a spaceship moving a 0.9c towards Earth. According to Bob, how fast is Carl moving relative to Earth?
  6. Physics

    The bond between protons and neutrons inside the atomic nucleus is formed by the strong interaction. In classical terms, we can think of it as protons and neutrons exchanging a "meson," a kind of fundamental particle between them. …
  7. Physics

    The earth moves around the sun in a nearly circular orbit of radius 1.50 x 1011 m. During the three summer months (an elapsed time of 7.89 x 106 s), the earth moves one-fourth of the distance around the sun. (a) What is the average …
  8. Physics

    What is the kinetic energy in MeV of a π–meson that lives 1.80×10-16 s as measured in the laboratory, and 0.840×10-16 s when at rest relative to an observer, given that its rest energy is 135 MeV?
  9. physics

    What is the kinetic energy in MeV of a π–meson that lives 1.80×10-16 s as measured in the laboratory, and 0.840×10-16 s when at rest relative to an observer, given that its rest energy is 135 MeV?
  10. Chemistry help

    The earth moves round the sun in one year.the average earth-sun distance is 1.5*10^11m given that the mass of the earth is 5.98*10^24kg (a):the angular momentum of the earth?

More Similar Questions