A positive charge of 50microCoulmbs is placed in an electric field of 50,000 N/C directed upward, what mass should the charge have to remain suspended in the air

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

probably not if net force is zero

3. dark matter

empty space could also be a simple vacuum