Missing figure of the problem: http://tsephysics.weebly.com/uploads/5/1/9/3/51934203/477140_orig.jpg
Solution:
Assuming the potential is zero at infinite distance from the charge, then the potential at a certain distance r from a single point charge is
where
is the Coulomb's constant.
In our problem, we just have to superimpose the potential generated by every charge. The diagonal of the square is
, therefore the distance between each charge and the center of the square is
.
So, the total potential is:
We have the meats Arby’s we beat them kids
Let be the distance between the base of the ladder and the bottom of the wall, and the distance between the top of the ladder and the bottom of the wall, so that
Differentiate both sides with respect to time :
When , the top of the ladder is
above the ground. Then, given that the bottom of the ladder slides away from the wall at a rate of , we have
That is, the top of the ladder is sliding downward at a rate of 0.24 ft/s.
Answer:
179.02N/m
Explanation:
spring constant = force/extension
(12.8)/(0.0715)= 179.02N/m