What is the relation between the direction of electric field and equipotential line at the same point

The direction of electric field and equipotential line at the same point are always PERPENDICULAR TO THE ELECTRIC FIELD.

Explanation:

Equipotential surface is a three dimensional part of equipotential lines.

Equipotential lines are a type of contour lines that is use to trace lines that have the same altitude on the map and the altitude is the electric potential.

Equipotential lines are always perpendicular to electric potential because the lines creates three dimension equipotential surface.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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