Doscience
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Homework Statement
In \alpha decay a nucleus X at rest decays to a daughter nucleus Y and an \alpha particle. Conservation of momentum and kinetic energy gives:
M_{\alpha}v_{\alpha}+M_{Y}v_{Y}=0
\frac{1}{2}M_{\alpha}v_{\alpha}^{2}+\frac{1}{2}M_{Y}v_{Y}^{2}=Q
Where the Q value is the available energy found through Q=(M(X)-M(Y)-M(\alpha))c^{2}
Show the kinetic energy of the two decay products are given by
E^{\alpha}_{k}=\frac{M_{Y}}{(M_{Y}+M_{\alpha})}Q
E^{Y}_{k}=\frac{M_{\alpha}}{(M_{Y}+M_{\alpha})}Q
Homework Equations
\frac{1}{2}M_{\alpha}v_{\alpha}^{2}+\frac{1}{2}M_{Y}v_{Y}^{2}=Q
M_{\alpha}v_{\alpha}+M_{Y}v_{Y}=0
Q=(M(X)-M(Y)-M(\alpha))c^{2}
E^{\alpha}_{k}=\frac{M_{Y}}{(M_{Y}+M_{\alpha})}Q
E^{Y}_{k}=\frac{M_{\alpha}}{(M_{Y}+M_{\alpha})}Q
The Attempt at a Solution
I have tried rearranging the energy equation to get E^{\alpha}_{k}=Q-\frac{1}{2}M_{Y}v_{Y}^{2}
since
E^{\alpha}_{k}=\frac{1}{2}M_{\alpha}v_{\alpha}^{2}
Then rearranging the conservation of momentum equation and substituting in for various variables but I can't get anything that looks like the required expressions. I know this is a fairly simple algebra exercise but I just can't figure out what to do so any advice or suggestions would be appreciated.