Downwind faster than the wind

Discussion in 'General Science & Technology' started by billvon, Jun 4, 2013.

  1. Aqueous Id flat Earth skeptic Valued Senior Member

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    I feel like I'm doing that even as we speak.
     
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  3. Motor Daddy Valued Senior Member

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    You're in the same boat as A.T.
     
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  5. Motor Daddy Valued Senior Member

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    I'm not a doctor, but I've read that people that smack themselves on the head with a wrench (like you're doing as we speak) are a few sandwiches short of a picnic. I'm just sayin'.
     
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  7. Aqueous Id flat Earth skeptic Valued Senior Member

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    I've got a cure for you practicing without a license. You can play car mechanic with the wind car. I have a question for you. If the wind presents a 100 N force on the blades of this thing, how much force is being applied to the mast at that location?
     
  8. A.T. Registered Member

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    Please state the whole question. What is given? What is asked?
     
  9. Motor Daddy Valued Senior Member

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    So it WAS you here earlier, and then you go away for a short time and come back and claim you just got here?
     
  10. Motor Daddy Valued Senior Member

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    As I stated earlier:

    You claim power=force*velocity.

    I lifted a 29 lb object at a velocity of 16 ft/s. How much work was done?
     
  11. Aqueous Id flat Earth skeptic Valued Senior Member

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    I have not been following the active discussion over the last 5 or 6 hours. I avoided the lengthier higher precision answer since you are squeamish about lots of facts and numbers.
     
  12. A.T. Registered Member

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    Not enough information to compute work.
     
  13. Aqueous Id flat Earth skeptic Valued Senior Member

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    That's correct MD, for all we know you are still doing the work, the way you stated it.
     
  14. billvon Valued Senior Member

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    Your action requires a power of .84 horsepower. (Note work does not equal power.)
     
  15. KitemanSA Registered Senior Member

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    Then it is an excellent boat and I'm in good company.
     
  16. KitemanSA Registered Senior Member

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    Can't know without the duration unless you assume an instantaneous velocity and a set g field.
     
  17. Alsee Registered Member

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    I will answer your question as soon as you answer my exactly equivalent question:

    I eat one banana per day.
    How many how many bananas have I eaten?

    By stating "I lifted a 29 lb object at a velocity of 16 ft/s", you are giving us power which is a rate which is exactly the same as my saying "I eat one banana per day".
    When you ask "How much work was done", you are asking for work which is a quantity which is exactly the same as my asking "How many how many bananas have I eaten".

    I'm not sure precisely what's tripping you up on "power=force*velocity", but the general theme running across all your posts seems to involve either equating a rate with a quantity, or difficulty tracking the relationship between them.

    Lifting a 100 lb rock by ten feet is a quantity of work. We can do that quantity of work at a rapid rate in 1/100th of a second with a very large horsepower motor moving the rock at high velocity, or we can can do that quantity of work at a very low rate in 1000 seconds with a very small horsepower motor moving the rock at low velocity.

    Time and velocity have no connection to the quantity of work, but time and velocity are central to power (which is the ability to preform work at a specified rate).
     
  18. Motor Daddy Valued Senior Member

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    How do you know you eat one banana per day? Is that a theory of yours or did you actually eat one?

    Same goes for velocity. How do you know the velocity if I didn't give it to you?
     
  19. Alsee Registered Member

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    Buh-bye troll
     
  20. Pete It's not rocket surgery Registered Senior Member

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    Motor Daddy has been given a 1-day ban for trolling and obstructing discussion. However, I've stepped outside my jurisdiction - I mistakenly thought this thread was in Physics and Maths, so MD's ban may yet be reversed.

    I'll ask for this diversion on the relationship between power and velocity to be moved to Physics and Maths.

    This is not appropriate, Alsee. Bans are not a cause for glee or gloating.

    Your irrelevant diversion is obstructing the discussion, Motor Daddy.

    Do you understand that Alsee's question is unanswerable, and that your Alsee was using to illustrate why your question is similarly unanswerable?
    Knowing the rate of bananas eaten per day doesn't tell you the total bananas eaten.
    Similarly, knowing power doesn't tell you work.
     
    Last edited: Jun 21, 2013
  21. KitemanSA Registered Senior Member

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    Thank you Pete.
     

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