Understanding Potential Difference in Terms of Electric Field and Distance

[Miike012]

I posted the question and the answer from the book inside the paint document.

My question is why is the answer not...

Δx = 3-1 = 2m
ΔE = 200-0 = 200V/m

ΔV = -(Area under E vs x graph) = -Δx*ΔE/2 = -200 V

 

[SammyS]

I posted the question and the answer from the book inside the paint document.

My question is why is the answer not...

Δx = 3-1 = 2m
ΔE = 200-0 = 200V/m

ΔV = -(Area under E vs x graph) = -Δx*ΔE/2 = -200 V

Your answer looks right to me.

What the book has for a solution is bizarre .

 

[CWatters]

The vertical axis isn't Volts it's V/m (eg the rate of change of V with distance).