Kinetic energy gain from potential difference with different mass and charge

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asheik234
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Homework Statement


A particle with a mass m and a charge Q is accelerated through a potential difference V, causing its kinetic energy to increase by an amount K. Another particle of mass m/5 and charge 2Q is accelerated through the same potential. How much kinetic energy does this second particle gain?


Homework Equations


Vq = U

(1/2)mv^2 = U;


The Attempt at a Solution


I can't find an equation that relates mass, charge and kinetic energy. Any help would be appreciated.
 
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It seems that you don't need to involve mass.

Remember, 1 volt = 1 joule of energy per coulomb
 
If Q*C = K;
then 2Q*C = 2K'

So the increase in kinetic energy is K, correct me if I'm wrong.
 
haruspex said:
I think you mean 2Q*C = K'

Then the kinetic energy doesn't change?
 
asheik234 said:
Then the kinetic energy doesn't change?
K' stands for the KE of the 2Q charge, right? (Just noticed the OP uses V, not C, so switching back to that here...)
If Q*V = K and 2Q*V = K' then what is the relationship between K and K'?
 
haruspex said:
K' stands for the KE of the 2Q charge, right? (Just noticed the OP uses V, not C, so switching back to that here...)
If Q*V = K and 2Q*V = K' then what is the relationship between K and K'?

So K' = 2K, right, because Q is proportional to KE.
 
asheik234 said:
So K' = 2K, right, because Q is proportional to KE.
Right, because KE is proportional to Q here.

Remember, 1 volt = 1 joule per coulomb