C. Mechanical, because temperature can cause solid objects to expand and contract, causing rocks to split apart.
To solve this problem we will apply the principles of energy conservation. On the one hand we have that the work done by the non-conservative force is equivalent to -30J while the work done by the conservative force is 50J.
This leads to the direct conclusion that the resulting energy is 20J.
The conservative force is linked to the movement caused by the sum of the two energies, therefore there is an increase in kinetic energy. The decrease in the mechanical energy of the system is directly due to the loss given by the non-conservative force, therefore there is a decrease in mechanical energy.
Therefore the correct answer is A. Kintetic energy increases and mechanical energy decreases.
<span>Brass is an <u>alloy</u>. An alloy
is a mixture of elements to form a unique material. Brass is a mixture of copper
and zinc and the percentage of each element depends on the desired material. It
has a higher malleability than bronze or zinc. Meaning that it can be bend
easily into it desired form.</span>
