Answer: B.Heat is never converted completely into mechanical energy.
Explanation:
According to the second principle of thermodynamics:
<em>"The amount of entropy in the universe tends to increase over time"
</em>
However the first formulation of this law (by Sadi Carnot) states:
<em>"There is an upper limit to the efficiency of conversion of heat to work, in a heat engine
"</em>
This means the heat cannot be completely transformed into mechanical energy in a machine. That is why a machine's effieciency is always less than 100%
Explanation:
According to Dalton's atomic theory, all the atoms are individual, all the atoms of the same element are identical in properties and mass, the compound is formed from two or more kinds of the atoms, all the matter is made up of small atoms and the chemical reaction is a rearrangement of the atoms.
The discoveries which contradicts the components of Dalton's atomic theory from the given discoveries are:
Nuclear reactions can change an atom of one element into an atom of another element.
Atoms of a given element can have different numbers of neutrons.
Atoms contain smaller particles: protons, neutrons, and electrons.
The melting of polar ice is one effect of the greenhouse effect, or also global warming.
The greenhouse effect, as defined by Merriam-Webster, is "the <span>warming of the surface and lower atmosphere of a planet (as Earth or Venus) that is caused by conversion of solar radiation into heat in a process involving selective transmission of short wave solar radiation by the atmosphere, its absorption by the planet's surface, and reradiation as infrared which is absorbed and partly reradiated back to the surface by atmospheric gases".
In short, "</span>the warming of the surface and lower atmosphere of a planet".
To solve this problem, it is necessary to apply the concepts related to the change of entropy in function of the Volume in two states due to the number of moles and the ideal gas constant, this can be expressed as
Where,
R = Gas constant
V = Volume (at each state)
At the same time the number of moles of gas would be determined by the ideal gas equation, that is,
Where,
P = Pressure
V = Volume
R = Gas Constant
T = Temperature
Using the value of moles to replace it in the first equation we have
Therefore the correct option is A.