Assume that 10 J of work is needed to push a charge,at rest,into an electric field.After the charge is released there,it flies back to its starting position and its kinetic energy there will be
A)zero.
B)5 J.
C)10 J.
D)more than 10 J.
E)impossible to predict without additional information.

Question

Quizplus · Accepted Answer

The work-energy principle states that the work done on an object is equal to the change in its kinetic energy. Since 10 J of work was done to move the charge into the electric field, it will have 10 J of kinetic energy when it returns to its starting position, assuming no energy is lost to other forces like friction.

Assume That 10 J of Work Is Needed to Push