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Question:

kela000
kela000
Student
Community / Jr. College

When NASA was communicating with astronauts on the moon, the time from sending radio signal on the earth to receiving on the moon was 1.28s.

Find the distance from earth to the moon. (the speed of radio waves is 3.00 x 10 to the 8th power m/s)

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Posted by kela000 on Tuesday September 22, 2009 at 8:36 AM and tagged with distance, math, speed, word problem.

Answers:

  1. krishna-agrawala
    krishna-agrawala Teacher
    Graduate School

    eNotes Editor

    The time taken for the radio signal to travel from Earth to Moon is 1.28 second.

    The speed of radio wave is 3.00*10^8 m/second The distance between earth and Moon is = (Time taken)*(Speed of radio wave) = 1.28*(3.00*10^8) = 3.84*10^8 meters = (3.84*10^8)/1000 kilometers = 384,000 kilometers. Answer: Distance from earth to moon is 384,000 kilometers.

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    Posted by krishna-agrawala on Tuesday September 22, 2009 at 9:10 AM

  2. kjcdb8er
    kjcdb8er Teacher

    eNotes Editor

    The formula for distance is speed x time.

    So d = 3.00 x 10^8 m/s x 1.28 s

    d = 3.84 x 10^8 m/s, or 384 x 10^6 m/s

    So the distance to the moon is 384 million meters.

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    Posted by kjcdb8er on Tuesday September 22, 2009 at 9:10 AM