Answer:
m = M (u-V)/(v-u)
Step-by-step explanation:
We know that:
[tex]mv + MV = (m+M)u = mu + Mu[/tex]
If we sum -mu to both sides of the equation we get:
[tex]mv -mu +MV =Mu + (mu-mu)=Mu[/tex]
Now let's sum -MV to both sides:
[tex]mv - mu = mv -mu + (MV-MV) = Mu -MV[/tex]
Now we can factor the m and M terms:
[tex]m(v - u) = M(u - V)[/tex]
Finally we can divide by v-u ***
[tex]m\frac{v-u}{v-u}=M\frac{u-V}{v-u}[/tex]
Since (v-u)/(v-u) =1
m = M (u-V)/(v-u)
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If u=v it will imply that V=u and tehrefore the two mases will travel with the same velocity to the same direction and no collision would take place
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