A 60-μC charge is held fixed at the origin and a −20-μC charge is held fixed on the x axis at a point x = 1.0 m. If a 10-μC charge is released from rest at a point x = 40 cm, what is its kinetic energy the instant it passes the point x = 70 cm?
A) 9.8 J
B) 7.8 J
C) 8.8 J
D) 6.9 J
E) 2.8 J

Question

Quizplus · Accepted Answer

The change in electric potential energy as the 10-μC charge moves from 40 cm to 70 cm is converted into kinetic energy. Calculate the potential energy at both points due to the other charges and find the difference. This difference is the kinetic energy gained.

A 60-μC Charge Is Held Fixed at the Origin and a −20-μC