Coulombs law says that the force between any two charges depends on the amount of charges and distance between them. This force is directly proportional to the magnitude of the two charges and inversely proportional to the distance between them.
where 
are charges, 
is the distance between them and k is the coulomb constant.
case 1:
case 2
case 3:
Comparing the 3 cases:
The maximum potential force according to coulombs law is between -1 charge and +3 charge separated by a distance of 100 pm.
I believe an Atom is a very powerful source, the basic unit of a chemical element. An atom is a source of nuclear energy.
But a molecule on the other hand isn't so different.
a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.
I hope that helps, have a fantastic day!
Answer:
1) The greatest height attained by the ball equals 20.387 meters.
2) The time it takes for the ball to reach 15 meters approximately equals 1 second.
Explanation:
The greatest height will be attained when the ball stop's in the air and starts falling back to the earth.
thus using third equation of kinematics we obtain the height attained as
where
'v' is the final speed of the ball
'u' is the initial speed of the ball
'a' is the acceleration that the ball is under which in this case equals 9.81 
's' is the distance it covers
Thus for maximum height applying the values in the equation we get
Using the same equation we can find the speed of the ball when it reaches 15 meters of height as
the time it takes to reduce the velocity to this value can be found by first equation of kinematics as
I believe it is -1.11 m/s^2. I will let you know if its correct
