Question

Figure 3.61 shows two negatively charged objects (with the same charge) and one positively charged object. What is the direction of the net electric force on the positively charged object? If the net force is zero, state this explicitly.

Short answer

Thedirection of the total forcewill be towards the positive x-direction (right).

Step-by-step solution

Identification of given data

There are two negatively charged objects and one positively charged object.

Concept of attractive and repulsive force

According to Coulomb’s law, two charged particle systems will exert an attractive or repulsive force towards each other if particles of the different or the same type of charges are there.

Determination of net electric force

The forces between the dissimilar charges (positive and negative) are attractive, whereas for the like charges it is repulsive.

From the above figure, one can see that the negative charge on the left-hand side of the positive charge is farther as compared to the negative charge on the right-hand side.

Both negative changes will exert an attractive force on the positive charge, while the magnitude of the electric force due to the charge on the right-hand side will be higher due to the smaller separation.

Thus the net force on the positive charge will be on the positive x-direction (right) since the positive charge will be attracted towards the negative charge on the right-hand side.

Therefore, the direction of the total force will be in the positive x-direction.