Alpha decay and its relationship to speed

[solaris123]

I need some explanation to what I must know in order to solve the next problem. A step by step process and mention of the particular concept I must know would be greatly appreciated as I must learn how to do this by june 8.
" In the alpha decay of a Uranium-238 nucleus, what is the ratio v/V, of the speed v of the emitted alpha particle and the speed V of the daughter nucleus?"
Thank you.

 

[WhoWee]

Why don't you post a brief explanation of what you do understand, followed by your ideas on how to proceed or more specific questions. I'm quite certain you will gain assistance if you put forth just a little more effort. Best of luck and welcome to PF!

 

[solaris123]

Ok, up to now I have concluded this must related to the amount of energy released in the process of the alpha decay as energy must be constant for any reaction. Knowing this I can use the mass of the resulting particles, the alpha and the daughter nucleaus, in order to find their velocity by using the kinetic energy.
Now, the problem is that I have no clue in the exact way the energy is distributed amongst the resulting particles or the amount of energy present to begin with, making my kinetic energy idea fail because I have no idea how to calculate this kinetic energy to begin with.
So yeah, I can't think of any other way to solve the problem and lackign that information I can't solve the problem.

 

[Astronuc]

In addition to conservation of energy, one also has conservation of momentum. Assume the U-238 is at rest.

 

[solaris123]

O_O, I feel like an idiot now... thank you kind sir, I had completely forgotten about that.