Recent content by SnowOwl18

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    Solving Wave Equations: Length, Frequency, Velocity

    there are 4 nodes in problem 1 and 5 in problem 2...but those don't include where the line begins on the horizontal axis..not sure if that part would count as a node.
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    Solving Wave Equations: Length, Frequency, Velocity

    nope...and i just tried that equation but it didn't work. i also tried what you gave for number 2 as well and that didn't work either...very peculiar, since they are the right equations and all. both questions have pictures that go with them, but they just show waves...i pasted the written...
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    Solving Wave Equations: Length, Frequency, Velocity

    Oh thank you for all of the equations...those look like helpful ways to solve them. I just tried #1 assuming wavelength= 4L ...so I did 2.7 x 4 = 10.8 . 342m/s / 10.8m = 31.6 Hz...but the computer said I was wrong. How is that so?
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    Solving Wave Equations: Length, Frequency, Velocity

    Ok, I understand waves and all, but for some reason I can't figure out how to manipulate the equations I know to solve these simple problems. 1. A standing sound wave in a pipe of length 2.70m is open at one end. Find the frequency of this harmonic. Use 342m/s for the speed of sound in air...
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    Calculating Force of 29.9kg Barbell Underwater

    Well...the buoyant force is the weight of the displaced water...aha! I have it. You subtract the buoyant force from the force that would normally be exerted above water (mg). Thank you for your help! :D
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    Calculating Force of 29.9kg Barbell Underwater

    Steel...I should've seen that. Well, what I tried to do was find the volume of steel using what I knew... 29.9kg= 7860kg/m^3 x V ...and for that value I got 0.0038m^3...and so I multiplied that by the density of water and then by gravity to get the buoyant force and got 37.28N, but the program...
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    Calculating Force of 29.9kg Barbell Underwater

    most equations say that the buoyant force= density of water x volume of object x gravity. but i do not know the volume...i do know that mass= density x volume...but if that is so, couldn't i theoretically just multiply the mass of the barbell by gravity to get the answer?
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    Calculate Airplane Weight | Help Solving Problem

    ah I see it now! Thanks so much :D
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    Calculating Force of 29.9kg Barbell Underwater

    -----A bodybuilder is holding a 29.9kg steel barbell above her head. How much force would she have to exert if the barbell were lifted underwater?---- Ok...I'm really not sure of this one. I thought maybe the answer was the weight of the barbell (mg) plus the atmospheric pressure at sea...
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    Calculate Airplane Weight | Help Solving Problem

    I have a modified version of Bernoulli's equation that seems to apply : P1-P2= 1/2 p (V2^2-V1^2) ...and I know how to plug in all the numbers, but I'm still not seeing how I can derive weight from that...even with the regular equation I still don't see how weight can be found. Sorry to sound so...
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    Calculate Airplane Weight | Help Solving Problem

    mm that makes sense...but I'm not sure how i could come up with the weight from that equation. is there another equation i could use with bernoulli's to get the weight? thanks so far :)
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    Calculate Airplane Weight | Help Solving Problem

    ----An airplane has an effective wing surface area of 15.9m^2 that is generating the lift force. In level flight the air speed over the top of the wings is 61.5m/s, while the air speed beneath the wings is 52.2m/s. What is the weight of the plane?---- I tried looking through my textbook and...
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    Solving Two Physics Problems: Weighing Rocks and Steel Barbells

    hmm so mass= density x volume. For the first problem I know the density and that the weight in air is twice that of in water...how do I use that equation if I don't actually know the mass though? Thanks for you're help so far :)
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    Solving Two Physics Problems: Weighing Rocks and Steel Barbells

    Alright, these two problems are driving me nuts: 1. ---To verify her suspicion that a rock specimen is hollow, a geologist weighs the specimen in air and in water. She finds that the specimen weighs twice as much in air as it does in water. The solid part of the specimen has a density of...
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