Recent content by Purple Baron

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    Change in internal Energy During Expansion of an Ideal Gas

    Well as it is constant pressure I could use the equation T_f=\frac{T_i V_f}{V_i} substituting initial temperature from the other equation gives T_f=\frac{PV_f}{R} and substitution into the internal energy equation gives \Delta U=\frac{3}{2}P(V_f-V_i) Is this ok? Thanks for the help everyone.
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    Change in internal Energy During Expansion of an Ideal Gas

    Homework Statement Derive an expression for the change in internal energy of 1 mol of an ideal gas for expansion from volume V_i to V_f under constant pressure of 1atm where \gamma = \frac{C_p}{C_v}=\frac{5}{3} Homework Equations \Delta U=\frac{3}{2}nR\Delta T PV=nRT The Attempt at a...
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    Solid Angle Rutherford Scattering

    Homework Statement derive an equation for the solid angle for a Rutherford scattering detector given a detcor window area of A and a distance to the detector of D for some scattering angle \phi given that d\Omega =2\pi sin\phi d\phi Homework Equations d\Omega =2\pi sin\phi d\phi A=Dd\phi The...
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    Age of Sample: U-235 & U-238 Abundances

    Thanks for that, I fixed the first equation.
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    Age of Sample: U-235 & U-238 Abundances

    Homework Statement The isostopc abundances of a sample is U-235 and U-238 are 0.72 and 99.27 respectively; what is the age of the sample? (assume isotope abundance was equal when sample was formed) Homework Equations \lambda=\frac{ln2}{ t_{\frac{1}{2}}} The Attempt at a Solution for U-238...
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    Alpha collision with unknown nucleus

    Ok, so that means m_x=m_y and dividing the energy equation by m_x gives \frac{1}{2}=\frac{m_xA^2}{2M_y}+\frac{B^2}{2} and if one defines \frac{m_x}{M_Y}=C then is it simply a case of solving the 3 equations for C and subbing in this ratio back into solve for M_y? Thanks
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    Alpha collision with unknown nucleus

    Ok, let me see if I've got this straight, if one defines the ratio \frac{p_Y}{p_x}=A and \frac{p_y}{p_x}=B ,and divides the momentum equations by p_x and the energy conservation equation by p_x^2 as you said, then one gets Acos\theta_Y=1-Bcos\theta_y , Asin\theta_Y=Bsin\theta_y and...
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    Alpha collision with unknown nucleus

    Oops, forgot to add that part in. So conservation of energy gives \frac{p_x^2}{2m_x}=\frac{p_y^2}{2m_y}+\frac{p_Y^2}{2M_Y} , I'm not quite sure I follow what you mean about the ratios. Thanks.
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    Joining the Physics Forum: A Second-Year Student's Perspective

    Hi guys, I'm Luke and currently on my second year of physics degree. I though it would be helpful to finally join this forum. Luke.
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    Alpha collision with unknown nucleus

    Homework Statement calculate the mass of an unknown nucleus of mass M_X (initially at rest) if it it is hit by an alpha particle of mass m_xand is deflected by 40 degrees, and the alpha particle is deflected by an angle of 70 degrees. Assume elastic collisions [/B]Homework Equations...
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