- #1
cookiemnstr510510
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Homework Statement
What is the speed of a proton that has been accelerated from rest through a potential difference of -1000V?
Homework Equations
ΔV=potential difference
V=U/q
Conservataion of energy
U=qEd (d is distance the proton is moving...i think)
The Attempt at a Solution
Here is my thought process with this problem:
ΔV=-1000V this means the change in electric potential is (-), doesn't tell us what V(initial) or V(final) is, but we know the difference between them is 1000
I know that V=U/q
For the proton going through this potential difference it follows conservation of energy:
Ki+Ui=Kf+Uf→0+qEd=1/2mpv2+0→qEd=1/2mpv2
here is where I get stuck...
it looks to me like we have one equation and two unknowns
the equation being:qEd=1/2mpv2
the unknowns: E and v
And I guess I am not even sure if Uf=0.