9cm is equal to what in mm

m = M (u-V)/(v-u)

Step-by-step explanation:

We know that:

If we sum -mu to both sides of the equation we get:

Now let's sum -MV  to both sides:

Now we can factor the m and M terms:

Finally we can divide by v-u ***

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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