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physics

Ek=p^2/2
E_k = p^2 / 2m,

where E_k = kinetic energy
p = momentum
m = mass

note you can easily check this is true by subbing in p=mv
Original post by picachu66499
Ek=p^2/2

What is the question? the formula itself? to show the validity of the equation? for what? quantum physics by any chance?

E_k = 1/2*m*v^2

is kinetic energy of a particle when it is in motion. Considering that a particle has a momentum, you have to use this formula:

p = m*v <=> v = p/m

Use the converted formula to put the speed v in the equation for E_k and you get the answer.

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