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A Physics Question
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| I'm sorry that title is vague. Anyway, I'm taking physics this year and I learned that if a fan and the sail the fan is blowing into are on the same overall machine in the same system, the machine won't move. I understand that it's because no energy is leaving/entering the overall system (I think), but does anyone else think this is strange? How is the total system determined? |
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Re: A Physics Question
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on 2006-02-23 10:37:10 (edited 2006-02-23 13:43:50)
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Think about it this way Sail Fan If the fan blows the sail, then the force exerted is like this Sail<(Being blown left by the fan) >Fan(blowing left, thereby causing itself to go right) because the fan is blowing air towards the sail, it would go away from the sail, and because the sail is blown by the fan, it would go away from the fan. Lastly, since the fan is exerting the force used both on the fan and on the sail, then the force exerted is equal, and nothing moves  |
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Re: A Physics Question
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Ok, thanks! ...So sailboats move because the wind isn't actually contained on the boat or attached to it, so there isn't an equal and opposite force... I think. ^.^ |