Recent content by Patrickas

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    What is the Width of the Central Maximum in Single Slit Diffraction?

    alright i seem to have chosen wrong m... i don't understand why is there a path difference of half the wave length then? I mean I understand the double slit interference- that the additional lengh 1 ray must go must be equal to full wave to get constructive interferance. But with single slit i...
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    What is the Width of the Central Maximum in Single Slit Diffraction?

    Homework Statement A single slit 10-4m wide(a) is illuminated by plane waves from helium-neon laser ( l = 6.328*10-7m). If the observing screen is 10m(D) away, determine the width of the central maximum(y). Homework Equations sin(alpha)=(m+0.5)*l/a tan(aplha)~sin(alpha)=y/2*D...
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    Calculating Potential & Kinetic Energies of a 80kg Man Swinging on a Swing

    O yea! Thanks! It should be much faster and easier to solve those problems now.
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    Calculating Potential & Kinetic Energies of a 80kg Man Swinging on a Swing

    Hey thanks for the help! I have been trying to solve this one for days! hehe
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    Calculating Potential & Kinetic Energies of a 80kg Man Swinging on a Swing

    T=60/15=4s t=4/12=1/3s So i know that W=kx^2/2 Well then i tried getting k, k=mg/l , now i needed the lengh of swings so i figured mv^2/r=mgr/l l=r^2g/v^2, now i need speed =D. v=s/t is s= 4*r? , or s=2*3.14*r? and t=1/3. Anyways i sense that something here is wrong. The numbers don't add up...
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    Calculating Potential & Kinetic Energies of a 80kg Man Swinging on a Swing

    yea, but there are a lot more people out there not from new york, who might know.
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    Calculating Potential & Kinetic Energies of a 80kg Man Swinging on a Swing

    oh c'mon! there must be someone out there knowing how to do this...
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    What is the Solution to a Function and Roots Problem?

    Cool! Thanks! I wonder hoe long will i remember this rule =]
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    What is the Solution to a Function and Roots Problem?

    Hmmm I'm guessing that the signs will change. Then i should get -√2+2+√2= 2 Right?
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    What is the Solution to a Function and Roots Problem?

    Homework Statement F(X)=√x F((F(2)-2)^2)+f(2) Homework Equations The Attempt at a Solution I get to √(-4√2 +8) ... that minus sign is annoying me =] any help?
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    Calculating Potential & Kinetic Energies of a 80kg Man Swinging on a Swing

    Homework Statement 80kg mass man is swinging on a swing. His amplitude is 1m. in 60 seconds he does 15 swings. Find the potential and kinetic energy after 1/12 period. Homework EquationsW(p)=mgh or kx^2/2 W(k)=mv^2/2 W(max)=Fr^2mg/2l The Attempt at a Solution i Found out that...
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    How much energy is needed for electrolysis to produce 2.5l of hydrogen?

    If anyone is interested how to solve it read along. :smile: "You have 0.1 mole of hydrogen gas produced (from pV=nRT) So far so good Multiply by Avogadro's number to find number of hydrogen molecules Each molecule needs 2 hydrogen atoms Each atom had a charge = 1.6 x 10^-19 C Multiply...
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    How much energy is needed for electrolysis to produce 2.5l of hydrogen?

    O maybe the answer to the problem will help - 0.13MJ
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