Question

if the electric field at a point is along south.the potential gradient is zero​

Answer 1

is your question -> if the electric field at a point is along south and the potential gradient is zero , is it correct statement or not ? otherwise this question is incomplete.

okay, let you ask about statement is correct or not.

first of all, understand , what is the meaning of potential gradient ?

potential gradient is nothing just rate of change of potential with respect to position. I mean, if we say potential gradient is zero, it means potential remains same with respect to position.

but here also given that electric field at a point is along south , it means electric field is present. but that point potential is constant. Nope, it's not correct statement.

if you know, electric field is negative of potential gradient. when potential gradient is zero then, definitely electric field at that point must be zero.

so, given statement is wrong.