physics

posted by .

Lunar astronauts placed a reflector on the Moon’s surface, off which a laser beam is periodically reflected. The distance to the Moon is calculated from the round trip time. The taken for the laser pulse to travel there and back again can be measured to 0.1 ns. What percent accuracy is this, given the average distance to the Moon is 3.84 X 108 m?

  • physics -

    .1 ns = 1 * 10^-10 m/s
    c = 3*10^8 m/s approx

    d = 2 * 3.84 * 10^8 = 7.68 *10^8 m
    time = d/c = 7.68/3 = 2.56 s

    percent = (10^-10/2.56) * 100
    = 10^-8/2.56
    = 10 * 10^-9 /2.56
    = 3.9 * 10^-9 percent

  • physics -

    99.99% of accuracy

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    The distance between earth and the moon can be determined from the time it takes for a laser beam to travel from earth to a reflector on the moon and back. If the round-trip time can be measured to an accuracy of 0.19 of a nanosecond …
  2. Physics please help!

    The distance between earth and the moon can be determined from the time it takes for a laser beam to travel from earth to a reflector on the moon and back. If the round-trip time can be measured to an accuracy of 0.19 of a nanosecond …
  3. Physics repost please clarify

    The distance between earth and the moon can be determined from the time it takes for a laser beam to travel from earth to a reflector on the moon and back. If the round-trip time can be measured to an accuracy of 0.19 of a nanosecond …
  4. Physics repost

    I apologise for reposting this question but it is still not working out for me. I know that: speed of light c=3.0x10^8 Time interval delta t=0.19x10^-9s The relationship between actual time and roudtrip distance is d=ct Also if there …
  5. physics

    Consider a pulse of laser light aimed at the Moon that bounces back to Earth. The distance between Earth and the Moon is 3.84 * 108 m. Show that the round-trip time for the light is 2.56 s.
  6. physics

    Consider a pulse of laser light aimed at the Moon that bounces back to Earth. The distance between Earth and the Moon is 3.84 * 108 m. Show that the round-trip time for the light is 2.56 s
  7. Physics

    One way to determine the distance to the moon is to bounce a laser beam off a mirror on its surface. How far away is the moon if it takes 2.56 seconds for the laser to "echo" off the moon?
  8. physics

    Consider a pulse of laser light aimed at the Moon that bounces back to Earth. The distance between Earth and the Moon is 3.84 * 108 m. Show that the round-trip time for the light is 2.56 s.
  9. Physics

    Help!! I would greatly appreciate help with this question. Consider a pulse of laser light aimed at the Moon that bounces back to Earth. The distance between Earth and the Moon is 3.84 * 108 m. Show that the round-trip time for the …
  10. Physics

    Lunar astronauts placed a reflector on the Moon’s surface, off which a laser beam is periodically reflected. The distance to the Moon is calculated from the round trip time. The taken for the laser pulse to travel there and back …

More Similar Questions