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For a figure showing electric lines of force, the field lines are crowded (closely spaced) near point A and widely spaced near point B, with the lines pointing from A towards B. Which of the following is correct? (E denotes electric field magnitude, V denotes electric potential.)
- E_A > E_B and V_A > V_B
- E_B > E_A and V_B > V_A
- E_A > E_B and V_A < V_B
- E_B > E_A and V_A > V_B
Correct answer: E_A > E_B and V_A > V_B
Solution
Where lines of force are closer together the electric field is stronger, so E_A > E_B (A has crowded lines). Field lines run from higher to lower potential; since the lines point from A to B, A is at higher potential, so V_A > V_B.
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