In hot warter or substant bc hot makes molecues go,s faster then all the rest
The change in the height of the object is 5.1 m.
<h3>Conservation of mechanical energy</h3>
The principle of conservation of mechanical energy states that the total energy of an isolated system is always conserved.
The change in the height of the object is calculated by applying the principle of conservation of mechanical energy as follows;
P.E = K.E

Thus, the change in the height of the object is 5.1 m.
Learn more about conservation of mechanical energy here: brainly.com/question/6852965
The thermal efficiency of a combustion system is simply
the ratio of heat out and heat in, that is:
efficiency = heat out / heat in
efficiency = 1030 J / 1540 J
efficiency = 0.669
<span>So the efficiency is 0.669</span>