Suppose two charges, one positive and one negative, are separated by a distance d. Where can two equipotential surfaces at different potentials intersect in the region near the charges?
a. halfway between the charges if the charges have the same magnitude
b. closer to the smaller negative charge than the larger positive charge if the charges are not equal
c. Equipotential surfaces at different potentials cannot intersect.
d. closer to the smaller positive charge than the larger negative charge if the charges are not equal
Question 2
Two equal magnitude forces are in opposite directions, and their lines of action are separated by distance d. These two forces are applied to a solid disk, which is mounted on a frictionless axle. If d is half the radius r of the disk, which of the following positions for the forces would give the most torque?
a. One force on a line touching the circumference of the disk and the other on a line halfway to the center.
b. One force on a line at a distance d from the center and the other on a line through the center of the disk.
c. One force on a line at a distance d/2 from the center of the disk and the other on a line at a distance d/2 on the opposite side of the center of the disk.
d. Since all the above orientations give the same torque, choose this answer.
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