Please give a quick explanation to which one is the right an

3. Three sets of cross sections of equipotential surfaces are shown, all covering the same region of space. Rank the magnitudes of the electric fields due to each, greatest first. 20 V 40 60 80 100-100 -10 V -30 -50 Rank: -140V -120 4. Which of the electric fields of the previous problem are directed down the page?

Solution

3) a > b =c (strength of electric field depends upon change in potential per unit length. In above three cases length/ region is same but change in potential is 80 V in a but 40 V in both b and c .

4) c ; direction of electric field is always directed towards decreasing value of potential equipotential lines. So, the electric field is directed upwards in above a and b but downwards in c.