Answer:
<em>The speed of the projectile when it impacts the ground is 1000 m/s</em>
Explanation:
<u>Vertical Launch</u>
When an object is launched vertically and upwards it starts to move at an initial speed vo, then the acceleration of gravity makes that speed to reduce until it reaches 0. The object has reached its maximum height. Then, it starts to move downwards in free fall, with initial speed zero and gradually increasing it until it reaches the ground level. We will demonstrate that the speed it has when impacts the ground is the same (and opposite) as the initial speed vo.
The speed when the object is moving upwards is given by

The time it takes to reach the maximum height is when vf=0, i.e.

solving for t

The maximum height reached is

Then, the object starts to fall. The object's height is given by

where t' is the time the object has traveled downwards. The height will be 0 again when

Solving for t'

We can see the time it takes to reach the maximum height is the same it takes to return to ground level. Of course, the speed when it happens is

Thus, the speed of the projectile when it impacts the ground is 1000 m/s
Answer:
Making a Hypothesis
Explanation:
-Research the subject of your question. Review the literature and find out as much as you can about previous information and discoveries surrounding your question.
-Develop an educated guess that answers your initial question. This is your hypothesis. Make a prediction based on your hypothesis and state it as a cause-effect relationship.
The question is missing, however, I guess the problem is asking for the value of the force acting between the two balls.
The Coulomb force between the two balls is:

where

is the Coulomb's constant,

is the intensity of the two charges, and

is the distance between them.
Substituting these numbers into the equation, we get

The force is repulsive, because the charges have same sign and so they repel each other.
Answer:
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