Physics

Problem

Two small insulating spheres carry charges

q_1 = +4.0\,\mu\text{C}

and

q_2

(unknown). They are released from rest

r_0 = 0.25\,\text{m}

apart but cannot approach closer than

r_f = 0.020\,\text{m}

because of their physical size. Exactly

5.0\,\text{J}

of electric potential energy is converted into kinetic energy as they move from

r_0

r_f

. What is

q_2

? a)

+3.0\,\mu\text{C}

-0.30\,\mu\text{C}

-3.0\,\mu\text{C}

-32\,\mu\text{C}