question_answer

The figure gives the electric potential V as a function of distance through five regions on \[x\]-axis. Which of the following is true for the electric field E in these regions [AMU 2000]

A)            \[{{E}_{1}}>{{E}_{2}}>{{E}_{3}}>{{E}_{4}}>{{E}_{5}}\]

B)            \[{{E}_{1}}={{E}_{3}}={{E}_{5}}\] and \[{{E}_{2}}<{{E}_{4}}\]

C)            \[{{E}_{2}}={{E}_{4}}={{E}_{5}}\] and \[{{E}_{1}}<{{E}_{3}}\]

D)            \[{{E}_{1}}<{{E}_{2}}<{{E}_{3}}<{{E}_{4}}<{{E}_{5}}\]

Correct Answer: B

Solution :

           Electric field in the region 1, 3 and 5 is zero i.e. \[{{E}_{\text{1}}}={{E}_{\text{3}}}={{E}_{\text{5}}}\] Slope of the line BC < Slope of the line DE i.e. \[{{E}_{\text{2}}}<{{E}_{\text{4}}}\]