Ranking the E-field from a graph alittle confused.

AI Thread Summary
The discussion focuses on ranking regions based on the magnitude of the x component of the electric field derived from the electric potential V as a function of x. The user initially believed that longer distances in the x direction indicated a greater electric field magnitude, which was incorrect. They also attempted to use the area under the curve to make their ranking, but that approach was also wrong. The correct method involves understanding that the electric field E is related to the slope of the potential V(x), with steeper slopes indicating stronger electric fields. The key takeaway is that the ranking should be based on the steepness of the potential graph rather than distance or area.
mr_coffee
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Figure 24-27 gives the electric potential V as a function of x.
Figure


(a) Rank the five regions according to the magnitude of the x component of the electric field within them, greatest first (use only the symbols > or =, for example 2=4>1=3>5).

I got the other 2 parts (b) and (c) right. What I thought was, the longer the space is in the x direction the bigger the magntude of the electric field. Which was wrong, i also tried to find the area under of the curve which was also wrong. When I tried to rank them from the area under the curve I got:
3>4=2>1>5
When i ranked them from the length fo the x distance, i got:
4>1=3=5>2

both wrong, what did i do wrong?
:bugeye:
 
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E=-\frac{dV(x)}{dx}

That means that the greater the slope of V(x), the greater the absolute value of E.
 
Awesome! thanks alot!
 
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