Recent content by xxiangel

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    I proving two Trig identities

    1. Cos x (sec x + cos x csc^2 x) = csc^2 x I got as far as this... 1 + cos^2 + cos/sin^2 = csc^2 2. tan x(sin x + cot x cos x) = sec x
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    Not sure how to do this temp and freq problem

    Can someone help me work these out!? 1) A sound travels 1,047 meters in 3 seconds in air. Find the air temperature. (Answer 31.3 degrees C??) 2) A guitar string plays a fundamental frequency of 400 Hz. Find the frequency played if the string were twice as long and twice as tight...
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    OUNT OF HEAT NEEDED TO CHANGE A SUBSTANCE FROM ONE PHASE TO ANOTHER

    One more question Andrew, you have been so hopeful already. How is water to steam considered vaporization in this problem? I thought water to steam was considered fusion, and steam to water was vaporization. Thats how the example problems are in my physics book. This has to do with Q4.
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    OUNT OF HEAT NEEDED TO CHANGE A SUBSTANCE FROM ONE PHASE TO ANOTHER

    How much heat must be absorbed by 1 kg of ice at -20 degrees Celcius to change it to steam at 130 degrees? This is the work that I came up with. Ice -20°C to Ice 0°C= q=mc(change in T)= 1kg x 2060 J/kg.Kx 20 degrees= 41200 J Ice 0 degrees to Water 0 degrees= Q= Hf x m= 334,000 j/kg x 1...
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    What Calculations Are Needed to Convert Steam to Water and Ice to Steam?

    Temperature Problems... Confused! please help! How much heat must be taken away from 400 grams of steam at 200 degrees to change it into water at 100 degrees? (Teacher says answer is -985,000 J) How much heat must be absorbed by 1 kg of ice at -20 degrees Celcius to change it to steam at 130...
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