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Velocity issues =(

  1. Sep 20, 2004 #1
    Hey guys


    um


    LIght from the Sun reaches Earth in 8.3 minutes .
    The velocity of light is 3 x 10 (8) meters per second<- <pretend this is a power>. How far is Earth from the sun?


    geez to get distance i have to multiply the speed vs the velocity

    in the answer key it says the answer is 2.5 but i need to know the steps to get there.. would someone please help?
     
  2. jcsd
  3. Sep 20, 2004 #2

    Math Is Hard

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    2.5 what? What units of measurement are you talking about?
     
    Last edited: Sep 20, 2004
  4. Sep 20, 2004 #3

    talking about m/s metres per second
     
  5. Sep 20, 2004 #4

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    Meters per sec is a measurement of rate not distance. If we're talking about distance, you need a measurement in meters (or kilometers or miles,etc.)
     
  6. Sep 20, 2004 #5

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    Distance is equal to rate(velocity) multiplied by time. Can you give this a try? I would suggest converting minutes to seconds before getting started.
     
  7. Sep 20, 2004 #6
    how would u solve this answer then because evidently my answer key is wrong
     
  8. Sep 20, 2004 #7
    in this case i'd have no problem doing it if not for the scientific notation how would i write that in a formula and solve it as well?
     
  9. Sep 20, 2004 #8
    the scientific notation is what throws me off and also it gets me thinkinga bout significant figures.. soo help? i'm so confused +__+
     
  10. Sep 20, 2004 #9

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    velocity is given as 3 x 108 m/seconds
    time is given as 8.3 minutes or 498 seconds

    you just need to multiply these
     
  11. Sep 20, 2004 #10

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    OK, kiddo. I think you can take it from here. I am going to bed.

    p.s. you can check your figures by googling "earth distance to sun"

    toodles.
     
  12. Sep 20, 2004 #11
    Time X Velocity = Distance
    s x m/s = m

    where m = metre and s = second.
     
  13. Sep 20, 2004 #12

    HallsofIvy

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    This is the second time you have posted this and you have been given a great deal of help. You say "in this case i'd have no problem doing it if not for the scientific notation". Okay, suppose the problem said that the speed of light was 3 meters per second and it took light 8.2 minutes to get to the earth. That has no scientific notation: what is the distance from the earth to the sun given that?
     
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