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    Question about gases and kinetic theory

    i have a question that I cannot solve; Show that the rms velocity of a sodium atom moving in a vaccum chamber at 300 kelvin is about 570 metres per second pV=nRT and 3pV=Nm<c^2>
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    Reduction Formulae

    Define I(n) by I(n) = integral of x^n / square root(1+x^2) dx. Evaluate I(0), I(1) and then establish the reduction formula I(n) = ((root2)-(n-1)I(n-2))/(n) for suitable values of n, which should be stated Here is my attempt I found I(0) first,and got the answer to be...
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    Impossible Integral

    1. integrate 1/(1+(xx-1)^0.5) I.E. Integrate 1 over the sqaure root of( x^2 - 1) 2. I started by rationalizing the fraction and then i split the equation into two. I THEN let x = root2 (tanh(u)) for the 1/(xx-2) fraction, and have no idea what to do from there :S
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    Lightning and Capacitance!

    1. The base of a cloud has an area of 2*10^7 metres squared and is on average 1km above the ground. treating the base of the cloud, the ground and the intervening air gap as a parallel plate capacitor, calculate the capacitance.[relative permittivity of air = 1.0] 2. I tried to say C...
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    De Broglie wavelength, Maximum kinetic energy, and smoke particles

    I have a few questions: 1. 'small smoke particles in air are seen under a low magnification microscope to move randomly at a speed of 0.10mm/s. The speed of sound in air is 330m/s. Estimate the mass of the smoke particles. I cannot make the link between speed of particle and speed of sound -...
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    Wave Problem

    I am stuck on a question about standing waves: 'The diagram below show's Melde's experiment and demonstartion of a stationary wave on a string' The string has 3 full wavelengths shown, and 3 points are marked: Point A is on an antinode, Point B is on the same antinode, but very...
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    Confused! X-ray spectrum

    Hello, I have studied X-ray emission when an electron beam is fired at a tungsten target - But when I was presented with the graph of Intensity versus wavelength, I was confused... I saw a curve, and on it there were spikes. What are these spikes, and why are they caused? Something to...
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    Hydrogen Spectrum - Help!

    Hi, I have a question concerning a hydrogen spectrum: There are 4 energy levels drawn: Starting from the top -1.4 * 10^-19 Joules -2.4 * 10^-19 Joules -5.4 * 10^-19 Joules -21.8 * 10^19 Joules 1st question: Going from the second level to the third from the top (from -2.4 to...
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    Water mechanics homework

    A cliff diver takes off horizontally from a cliff face 26.5 metres above the surface of the water. In the course of his flight, he travels 8 metres forwards, of which all but the last 1.5 metres of horizontal motion is above rock. In other words, he travels 6.5 metres in the air horizontally...
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    Radiation and electroscope

    If ultraviolet radiation is shone onto a freshly-cleaned zinc cap of an uncharged leaf electroscope, explain why the emission of electrons will soon stop I understand it is about the photoelectric effect, but I am not sure why the emission will ever stop... Thank You in advance!:biggrin: