Answer:
d = 90 ft
Explanation:
Here in each swing the distance sweeps by the swing is half of the initial distance that it will move
So here we can say that total distance in whole motion is given as
since it is half of the distance that it will move in each swing so it would be a geometric progression with common ratio of 1/2
so sum of such GP is given by the formula
As we know that two charges exert force on each other when they are placed near to each other
The force between two charges is given as
here we know that
= two different point charges
r = distance between two point charges
also we know that two similar charges always repel each other while two opposite charges always attract each other
so here correct answer would be
<em>A. A positive and negative charge attract each other.</em>