Electric field strength vs electric potential? Watch

Uni12345678
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I was doing a multiple choice question, and one of the statements i thought was true is actually false, and im not sure why, could someone explain why the
Electric potential is not zero whenever the electric field strength is zero ??
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Dowel
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(Original post by Uni12345678)
I was doing a multiple choice question, and one of the statements i thought was true is actually false, and im not sure why, could someone explain why the
Electric potential is not zero whenever the electric field strength is zero ??
It's because electric field strength is a vector quantity and electric potential is a scalar quantity.

we know Electric field strength = 0
and that E = -dV/dr
which implies that V is constant.
so E is 0 but the change in electric potential can be any constant value.
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Uni12345678
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(Original post by Dowel)
It's because electric field strength is a vector quantity and electric potential is a scalar quantity.

we know Electric field strength = 0
and that E = -dV/dr
which implies that V is constant.
so E is 0 but the change in electric potential can be any constant value.
I don't understand.... surely if a certain amount of energy is required per unit mass (i.e. Potential) to move it from one infinity to that point in the field, there must be a certain force doing work on it due to the field?? would this apply to gravitational fields as well then ??
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Eimmanuel
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(Original post by Uni12345678)
I was doing a multiple choice question, and one of the statements i thought was true is actually false, and im not sure why, could someone explain why the
Electric potential is not zero whenever the electric field strength is zero ??
It would be good if you can post your thinking why you think the false statement is true in your opinion.

A good example to show that electric potential is not zero whenever the electric field strength is zero is a system of two positive charges of similar magnitude separated by a distance say d. The electric field is zero at the d/2 but the electric potential is not zero.

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Uni12345678
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(Original post by Eimmanuel)
It would be good if you can post your thinking why you think the false statement is true in your opinion.

A good example to show that electric potential is not zero whenever the electric field strength is zero is a system of two positive charges of similar magnitude separated by a distance say d. The electric field is zero at the d/2 but the electric potential is not zero.

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since gravity is always attractive, this wont apply for gravitational fields right?
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Eimmanuel
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(Original post by Uni12345678)
since gravity is always attractive, this wont apply for gravitational fields right?

It depends on how you view it. It is somehow the opposite.


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This is the “attractive scenario” between two opposite charges.

Attachment 657232657234

This is the “attractive scenario” between two masses.
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