The answer is A. waterfall
To be considered as an engine , it should be a Man-made objects that could be used to produce power that creates motions.
From all the options above could be used to produce such power, but the waterfall is not made by mandkind
Answer:
<em>W= 47</em>
Explanation:
Given:
m = 72 kg
F = 165 N along horizontal
s = 2.8 m
\mu = 0.21
The net force acting on the box is
W= 165-(0.21 * 72 * 9.81)) * 2.8
W= 46,68384
W= 47
They are both good conductors if both heat and electricity due to the sea of delocalized electrons that is floating around without getting bonded to an atom.
Such electrons can flow around freely to conduct heat and electricity.
Heat is kinda like sound (because it's a form of kinetic energy). More energy is the effect of higher tempetures, hence they vibrate faster. Because of this sound waves can travel at a faster rate. Hope this helped :)