Recent content by twinklestar28

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    Angles in momentum four vectors

    I put them both positive first and then i changed it, i think I am thinking in the one dimension so I am seeing the second photon in negative y quadrant, but looking in the x,y,z plane i think it would be positive, the signs r what i am most unsure of, is the rest correct?
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    Angles in momentum four vectors

    I was finding the magnitude, sorry got confused, would it simply be pcosa for x -psina for y
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    Angles in momentum four vectors

    x component = (psina)^2 y component=(pcosa)^2
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    Angles in momentum four vectors

    they are my initial vectors that i came up with, but i changed theta 2 into 180 because it is in the rest frame and also expressed E2 in E1 since in the rest frame they are equal but opposite, am i completely off the track here? or am i getting close... :S
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    Angles in momentum four vectors

    oo ok can u check if my new vectors are correct please? photon 1= (E1 sina, E1 cos a , 0 , E1) Photon 2= (-E2 sinθ2 , -E2 cos θ2 , 0 , E2) = (0,E1,0,-E1) using E1+E2=0 and since they are photons E=p are these right, especially the signs?
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    Determine resolution of use by modelling it as single slit

    O ok so the equation would be I=Iosin^2((π/λ)asinθ-∅)/ ((π/λ)asinθ-∅)^2 it gives a hint to consider the intensity halfway between the peaks of the two images so i did ((π/λ)asin(θ-∅)) = ∏/2 but where do i put the intensity change of 0.2% to get (θ-∅) = 0.00015?
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    Final temperature in reversible expansion

    Homework Statement One mole of an ideal monatomic gas initially at volume Vi and temperature 1000k expands to a final volume Cvi in three reversible steps: 1) isothermal expansion from Vi to aVi, 2) adiabatic expansion from aVi to bVi and 3) isothermal expansion from bVi to Cvi In terms...
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    Determine resolution of use by modelling it as single slit

    Homework Statement Model the pupil of the eye using a single slit. If the eye is able to notice changes in intensity of 20% show that it can distinguish two objects separated by an angle of 0.00015 radians if =500nm and diameter=4mm. Homework Equations I=Iosin^2((π/λ)asinθ)/...
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    Calculating kinetic energy density of wavepacket in deep water waves

    Assume that an orca can generate a wavepacket which is half a sine wave. Show that the kinetic energy density in this wave can be written U= ρgAλ/(32(π^2)) 2. Homework Equations mass per unit length=∫ρ dxdy KE=1/2mv^2 3. The Attempt at a Solution I'm confused on what to use...
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    Angles in momentum four vectors

    sorry the angle is meant to be cos θ = β^2-1+β^2sin^2a / 1-β^2cos^2a I forgot the β in the first part of the fraction..
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    Angles in momentum four vectors

    ok so if i didn't sub in the values my vectors would be in the rest frame: Photon 1 = (E1 sina, E1 cos a , 0 , E1) Photon 2 = (-E2 sinθ , -E2 cos θ , 0 , E2) a and θ is what they've asked for in the question, so to get the lab frame i use the lorentz transformation but i then have to...
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    Calculating kinetic energy density of wavepacket in deep water waves

    Homework Statement Assume that an orca can generate a wavepacket which is half a sine wave. Show that the kinetic energy density in this wave can be written U= ρgAλ/(32(π^2)) Homework Equations mass per unit length=∫ρ dxdy KE=1/2mv^2 The Attempt at a Solution I'm confused...
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    Determining interference pattern for two loudspeakers

    Homework Statement Two loudspeakers, at the same height are 2m apart and in phase with each other.Both emit 705Hz sound waves into a room. A listener stands 5m in front of the loudspeakers and 2m to one side of the centre. a) Is the interference pattern at this point...
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