7. Now reset the balloon. Again, collect the blue negative charges from the sweater, by rubbing the balloon on the sweater. Even bring the balloon close to the wall again. What do you notice about the movement of the negative charges in comparison to the positive charges? Explain why.
When resetting the balloon and rubbing it on the sweater to collect negative charges again, and then bringing it close to the wall, we will notice that the negative charges on the balloon will once again be attracted to the positive charges on the wall.
In comparison to the positive charges, the negative charges on the balloon will move towards the positive charges on the wall. This is because opposite charges attract each other. As the balloon gains a surplus of negative charges from the sweater, it becomes negatively charged. When brought close to the wall, the positive charges on the wall will attract the negative charges on the balloon, causing them to move towards the wall. Conversely, the positive charges on the wall will repel the positive charges on the balloon, so they will not be attracted to each other.