Answer:
Explanation:
information we know:
Total force:
Weight:
distance:
vertical component of the force:
-------------
In this case we need the formulas to calculate the components of the force (because to calculate the work we need the horizontal component of the force).
horizontal component:
vertical component:
but from the given information we know that
so, equation these two and
and we know the force , thus:
now we clear for
the angle to the horizontal is 15.466°, with this information we can calculate the horizontal component of the force:
whith this horizontal component we calculate the work to move the crate a distance of 4 m:
the work done is W=173.48J
Answer:
ΔS total ≥ 0 (ΔS total = 0 if the process is carried out reversibly in the surroundings)
Explanation:
Assuming that the entropy change in the aluminium bar is due to heat exchange with the surroundings ( the lake) , then the entropy change of the aluminium bar is, according to the second law of thermodynamics, :
ΔS al ≥ ∫dQ/T
if the heat transfer is carried out reversibly
ΔS al =∫dQ/T
in the surroundings
ΔS surr ≥ -∫dQ/T = -ΔS al → ΔS surr ≥ -ΔS al = - (-1238 J/K) = 1238 J/K
the total entropy change will be
ΔS total = ΔS al + ΔS surr
ΔS total ≥ ΔS al + (-ΔS al) =
ΔS total ≥ 0
the total entropy change will be ΔS total = 0 if the process is carried out reversibly in the surroundings
About a mil sience 2014-2015
If you remember the formula for potential energy,
then this question is a piece-o-cake.
<em>Potential energy = (mass) x (<u>acceleration of gravity</u>) x (height) .</em>
-- The object's mass is the same everywhere.
-- You said that the height is the same both times.
-- How about the acceleration of gravity ?
Compared to gravity on Earth, it's only 16.5 percent as much on the Moon.
So naturally, from the formula, you'd expect the Potential Energy to be less
on the Moon.
The universe believed to be has no limit in space and the elements, molecules and different kind of gases are found in this area. So the percentage of that is believed that and ordinary atom can be detected is C. 3% i hope you understand my answer.