D. Redefine the machine’s system boundaries.
The Law of Conservation of Energy states that energy can't be created not destroyed. Energy, however, can be changed from one form to another. The law applies to isolated systems only. By redefining and expanding the system (including all factors affecting it) , the machine's ability to do work should improve.
Explanation:
The Coulomb's law states that the magnitude of each of the electric forces between two point-at-rest charges is directly proportional to the product of the magnitude of both charges and inversely proportional to the square of the distance that separates them:

In this case we have an electron (-e) and a proton (e), so:

In this case, the electric force is negative, therefore, the force is repulsive and its magnitude is:

Answer:
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Explanation:
simple pendulum with no friction, mechanical energy is conserved. Total mechanical energy is a combination of kinetic energy and gravitational potential energy. As the pendulum swings back and forth, there is a constant exchange between kinetic energy and gravitational potential energy.
The force the escaping gas exerts of the rocket is 10.42 N.
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Force escaping gas exerts</h3>
The force the escaping gas exerts of the rocket is calculated as follows;
F = m(v - u)/t
where;
- m is mass of the rocket
- v is the final velocity of the rocket
- u is the initial velocity of the rocket
- t is time of motion
F = (0.25)(40 - 15)/0.6
F = 10.42 N
Thus, the force the escaping gas exerts of the rocket is 10.42 N.
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