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We have two equations
delta EP = -W
V = -Ed
Now, to my understanding for the second equation (E = -V/d) since its a vector quantity, we need to make it have direction
Therefore, if we substitute values E = -50V / 5 m = -10 N/C
We add in the negative sign to the equation because generally:
A proton would move DOWN, therefore the negative sign represents down
-------------------(+)
-------------------(-)
But the confusion stems from the second equation
-------------------(+)
A
B
-------------------(-)
If we have a proton that moves from A to B delta EP would be negative
So -d EP = -W
Work done is positive
But if we move it from point B to A, we exert force on it and therefore work done is negative (according to the equation)
This is extremely weird for me though, because in the first equation we're assuming down is negative and up in positive (like we have been for the rest of the units we've learned)
Yet for the second equation, we assume the exact opposite! Can someone clear up my confusion?
Thanks
delta EP = -W
V = -Ed
Now, to my understanding for the second equation (E = -V/d) since its a vector quantity, we need to make it have direction
Therefore, if we substitute values E = -50V / 5 m = -10 N/C
We add in the negative sign to the equation because generally:
A proton would move DOWN, therefore the negative sign represents down
-------------------(+)
-------------------(-)
But the confusion stems from the second equation
-------------------(+)
A
B
-------------------(-)
If we have a proton that moves from A to B delta EP would be negative
So -d EP = -W
Work done is positive
But if we move it from point B to A, we exert force on it and therefore work done is negative (according to the equation)
This is extremely weird for me though, because in the first equation we're assuming down is negative and up in positive (like we have been for the rest of the units we've learned)
Yet for the second equation, we assume the exact opposite! Can someone clear up my confusion?
Thanks