Kinetic Energies of Particles in Nuclear Decay

[lifeiseasy]

Homework Statement

A stationary uranium-238 nucleus undergoes alpha-decay. What is the ratio of the daughter nucleus to that of the alpha-particle?

P.S. It's a practice problem for which I had the final answer, but I'm not sure how to reach it.

Homework Equations

I guess it's based on conservation of energy. I'm unsure of the equations, though.
1/2 mv^2 for K.E.

The Attempt at a Solution

Sorry, I just don't know how to start.

 

[py1sl]

the question isn't really clear. Are you trying to find the ratio of kinetic energy of the daughter nucleus to the alpha particle? I am not exactly sure if this is right or what level you are studying at but my approach would be
firstly work out the rest mass of the U238, next you find the daughter nucleus and work out its rest mass, followed by rest mass of the alpha particle, the difference should be what has been converted to KE