10 points: Physics 101 Magnetic Fields Homework Q's

Question

Hey guys, since my text doesn't give solutions to HW q's I need something to check my answers against ... so here it goes:

1) Find the magnitiude and sign of a electric charge of a 100V point charge .35m away.

2) Find the charge on two small balls that are identical. The masses of each ball can be ignored. They are 2m away from each other (measured from the center of one ball to the center of the other). The force between them is 36N.

Answer 1

There is something wrong with your Homework Questions. First, you have a title of Magnetic fields Homework questions but as I look it, it looks like  that number 1 is talking about the electric potential at a certain point. Second, you have to modify question number 1.

Modifying question number 1; It should be like this: " Find the magnitude and sign of an electric charge that sets up an electric potential of 100 volts at 0.35 m away.  How to answer number 1:Let V=electric potential due to a point charge,  K= 9,000,000,000Nmm/CC, Q = the magnitude of the electric charge, R= distance between the electric charge and the point where the electric potential is known to be 100 volts. Use the formula:  V= [(KQ)/R]. Q=VR/K. To answer number 2: Q=squareroot of (Fmultipllied by squared of the distance/K)