A point charge and a point charge are brought from infinity to a separation of

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

+4.0\,\mu\text{C}

point charge and a

-4.0\,\mu\text{C}

point charge are brought from infinity to a separation of

0.10\,\text{m}

. What is the change in electric potential energy

\Delta U

of the two–charge system? (Use

k=8.99\times10^{9}\,\text{N\,m}^2\!\,/\!\,\text{C}^2

.) (a)

+1.44\,\text{J}

(b)

-1.44\,\text{J}

(c)

-0.72\,\text{J}

(d)

-14.4\,\text{J}