Please help, Express kinetic energy in terms of m and p?

AI Thread Summary
Kinetic energy can be expressed in terms of mass and momentum by starting with the definitions of momentum (p = mv) and kinetic energy (T = 1/2 mv^2). By substituting velocity (v = p/m) into the kinetic energy formula, it can be rewritten as T = 1/2 m (p/m)^2. Simplifying this leads to T = 1/2 (p^2/m). This transformation shows the relationship between kinetic energy, mass, and momentum clearly. The final expression for kinetic energy in terms of mass and momentum is T = p^2 / (2m).
belleamie
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Hi, I think my brain froze and I'm not seeing it
the problem is

the momentum is defined as
p=mv=m(dx/dt)
express the kinetic energy in terms of m and p

~ Now I know kinetic = T= (1/2)mv^2
and that P=mv
I figured that it must be t= (1/2)p^2
till i realized that I'm missing in terms of m. I just got stumped
 
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T= (1/2)p^2

You know p=mv, so p^2 gives (mv)^2

T=/= (1/2)(mv)^2

where =/= represents 'is not equal to'

I suspect that you will kick yourself when it dawns on you.
 
p=mv -> v=p/m

T=1/2*m*v^2

T=1/2*m(p/m)^2 -> T=1/2((p^2)/m)
 
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