Question

Some equipotential surface are shown in the figure. The magnitude and directions of the electric field is

• A. $100V/m$ making angle ${120}^o$ with the x-axis
• B. $100V/m$ making angle ${60}^o$ with the x-axis
• C. $200V/m$ making angle ${120}^o$ with the x-axis
• D. None of the above

Answer 1

The correct option is C $200V/m$ making angle ${120}^o$ with the x-axis

Perpendicular distance between equipotential surfaces:
$d=10sin{30}^o=5cm$
$E=\frac{\Delta V}{d}=\frac{30-20}{5/100}=200V{m}^{-1}$
Direction of electric field will be in the direction of decreasing potential