Physics

Problem

1.5\,\text{g}

latex sphere is given an unknown charge and released in a uniform electric field of

6.0\times10^{4}\,\text{N}\!/\!\text{C}

directed upward. What charge (magnitude and sign) must the sphere have so that it hovers at rest in the field? a)

+2.5\times10^{-4}\,\text{C}

+2.5\times10^{-8}\,\text{C}

-2.5\times10^{-7}\,\text{C}

+2.5\times10^{-7}\,\text{C}