Voltage difference causes charge to flow from?

Voltage difference causes charge to flow from higher potential to that of a lower potential.

Explanation:

Voltage Difference:

It is work done per unit charge in moving a charge from one point to another point.

V = Voltage difference

W = Work done

Q = Charge

Then,

unit : Volt or Joule/Coulomb

Flow of charge :

A free positive charge move from a region of higher potential to that of lower potential whereas a free negative charge moves from lower potential region to a higher potential.

Thus, a voltage difference is required for the flow of charge.

Direction of conventional current is from positive terminal to negative terminal.

Direction of electron is from negative to positive.

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.