The next step in Bobby's procedure is to touch the balloons with a metal rod and allow them to settle, and then to rub them 10 times with animal fur. Which result should he expect, and why?
(1 point)
The balloons will hang at the same elevation, because electrical repulsion is an unvarying phenomenon which results from the existence of charge and not its quantity.
The balloons will hang at a greater elevation, because they will have greater charges so the force of electrical repulsion between them will be greater.
The balloons will hang at a smaller elevation, because more thoroughly rubbing them will more completely remove their charges, reducing the electrical repulsion between them.
The balloons will hang straight down or more closely together, because a larger number of rubs with fur will give them opposite rather than like electrical charges
The correct answer is: The balloons will hang at a smaller elevation, because more thoroughly rubbing them will more completely remove their charges, reducing the electrical repulsion between them.
Rubbing the balloons with animal fur will transfer electrons between the balloons and the fur, resulting in the balloons acquiring an opposite charge to the fur (one balloon becomes positively charged and the other becomes negatively charged). When the balloons are touched with a metal rod, any remaining excess charge will neutralize, causing the balloons to settle and hang at a smaller elevation due to the reduced electrical repulsion between them.