B, heat, is the correct answer. Heat is represented by a capital q in thermodynamic equations.
Explanation:
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Answer:
So, the correct answer is <em><u>the strong nuclear force</u></em>. It actually pulls together nuetrons and protons that are in the nucleus. At very tiny distances only, like those inside the nucleus, so, this strong force succeded in dealing with the electromagnetic force, and it basically stops the electrical repulsion of protons from blowing apart the nucleus.
<u><em>Mark as brainlies please, I need a few more :D</em></u>
In any case, your mass would be<em> 68 kg </em>no matter what
Answer: The force constant k is 10600 kg/s^2
Step by step:
Use the law of energy conservation. When the elevator hits the spring, it has a certain kinetic and a potential energy. When the elevator reaches the point of still stand the kinetic and potential energies have been transformed to work performed by the elevator in the form of friction (brake clamp) and loading the spring.
Let us define the vertical height axis as having two points: h=2m at the point of elevator hitting the spring, and h=0m at the point of stopping.
The total energy at the point h=2m is:

The total energy at the point h=0m is:

The two Energy values are to be equal (by law of energy conservation), which allows us to determine the only unknown, namely the force constant k:
