Three point charges are arranged in a line. charge q3=+5.00 nc and is located at the origin. charge q2=-3.00 nc and is located at x=+4.00 cm. charge q1 is located at x+2.00 cm. what is the magnitude of q1 if the net force on q3 is zero

Explanation:

Electrostatic Forces

The force exerted between two point charges and separated a distance d is given by Coulomb's formula

The forces are attractive if the charges have different signs and repulsive if they have equal signs.

The problem described in the question locates three point charges in a straight line. The charges have the values shown below

The distance between and is

The distance between and is

We must find the value of such that

Applying Coulomb's formula for is

Now for

If the total force on is zero, both forces must be equal. Note that being q2 negative, the force on q3 is to the right. The force exerted by q1 must go to the left, thus q1 must be positive. Equating the forces we have:

Simplfying and solving for