1. Four identical, positive, point charges of magnitude Q are placed at the vertices of a [1 mark]
square of side 2d. What is the electric potential produced at the centre of the square by
the four charges?
+Q
+O
2d
2d
A. 0
4kQ
B.
d
V2kQ
C.
d
D. 277kQ

Review multiple-concept example 7 in this chapter as an aid in solving this problem. in a fast-pitch softball game the pitcher is impressive to watch, as she delivers a pitch by rapidly whirling her arm around so that the ball in her hand moves in a circle. in one instance, the radius of the circle is 0.626 m. at one point on this circle, the ball has an angular acceleration of 66.1 rad/s2 and an angular speed of 12.6 rad/s. (a) find the magnitude of the total acceleration (centripetal plus tangential) of the ball. (b) determine the angle of the total acceleration relative to the radial direction.