Question

In example 20.3 in the text, the net force on a 1.0 nC charge located between two 10 nC charges is calculated. How would the answer change if the two 10 nC charges were replaced by two -30 nC charges, leaving the 1.0 nC charge the same

Answer 1

The answer would not change as long as the distance remains the same.

Step-by-step explanation:

The net force on a charge can be calculated using Coulomb's law, which states that the force between two charges is directly proportional to their magnitudes and inversely proportional to the square of the distance between them.

In the given example, the net force on a 1.0 nC charge located between two 10 nC charges is calculated. If the two 10 nC charges were replaced by two -30 nC charges, the magnitude of the forces between the charges would change, but the net force on the 1.0 nC charge would remain the same as long as the distance between the charges and the 1.0 nC charge remains the same.

Answer 2

The forces experienced by the middle particle are attractive, and the net force will remain the same (0) if and only if the distances of the sides particles to the middle particle are the same.

Explanation:

In example 20.3 the forces experienced by the middle particle are repulsive because all the particles are positive, for the case in which the particles on the sides are replaced for negative charge particles the forces experienced by the middle particle are attractive. Regarding the net force, because we don't know the distances we can not give a definitive answer, what we can say is that if the distances from the middle particle to the sides particles are the same the net force is zero for both cases (remain unchanged).