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Electric potential graph analysis

  • Thread starter freshcoast
  • Start date
  • #1
185
1

Homework Statement


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Homework Equations



ΔU = -q∫E * ds

The Attempt at a Solution



Just by looking at the graph I am thinking, if I solve for E using the equation above, the number would be always negative therefore I can conclude that the electric field at any x position would be negative and the graph will look the same it will be just inverted. (-y values)

I don't know if this is the correct way to look at the problem or if I have to use energy conservation but any help would be much appreciated.

Thanks!
 
Last edited:

Answers and Replies

  • #2
1,540
134
Ex = -dV/dx =negative of the slope of V-x graph.

What is the slope of graph between 0 and 1,1 and 3,3 and 4 ?
 
  • #3
185
1
between 0 and 1, the slope is positive, 1 and 3 the slope is zero, 3 and 4 the slope is negative.

So if I use that equation you posted, between 0 and 1, the electric field will be negative, between 1 and 3 the electric field remains negative and then when x is between 3 and 4 the slope will be positive?
 
  • #4
1,540
134
between 0 and 1, the slope is positive, 1 and 3 the slope is zero, 3 and 4 the slope is negative.

So if I use that equation you posted, between 0 and 1, the electric field will be negative, between 1 and 3 the electric field remains negative and then when x is between 3 and 4 the slope will be positive?
Recheck your reasoning
 
  • #5
185
1
Oh, between 1 and 3 electric field is zero. 0 and 1 V slope is positive therefore efield is negative, 3 and 4 v slope is negative therefore efield is positive.
 
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