1. A particle that carries a net charge of 77.8C77.8C is held in a constant electric field that is uniform over the entire region. The electric field vector is oriented 55.255.2 clockwise from the vertical axis, as shown in the figure. If the magnitude of the electric field is 7.32N/C7.32N/C, how much work is done by the electric field as the particle is made to move a distance of =0.156m=0.156m straightup?

What is the potential difference between the particle's initial and final positions?

2. Three point charges, 1=22.4C, 2=38.6C,, and 3=87.3C, are arranged as shown in the figure. The lengths and both equal 20.1cm. Calculate the electric potential at pointA.