Answer:
Work: 4.0 kJ, heat: 4.25 kJ
Explanation:
For a gas transformation at constant pressure, the work done by the gas is given by

where in this case we have:
is the pressure
is the initial volume
is the final volume
Substituting,

The 1st law of thermodynamics also states that

where
is the change in internal energy of the gas
Q is the heat absorbed by the gas
Here we know that

Therefore we can re-arrange the equation to find the heat absorbed by the gas:

Weight = (mass) x (gravity)
Weight = (7.0 kg) x (gravity)
On Earth, where (gravity) is roughly 10 N/kg . . .
Weight = (7.0 kg) x (roughly 10 N/kg)
Weight = roughly 70 Newtons
That's <em>B </em>on Earth.
It would be some other number on other bodies.
The triangle <span>in the first law of thermodynamics, represents energy that moves from a hot object to a cooler object.</span>
Answer:
<h3>The answer is 1400 J</h3>
Explanation:
The potential energy of a body can be found by using the formula
PE = mgh
where
m is the mass
h is the height
g is the acceleration due to gravity which is 10 m/s²
From the question we have
PE = 20 × 10 × 7
We have the final answer as
<h3>1400 J</h3>
Hope this helps you
Directly most of alternative energy is gained from water. But eventually almost all energy on earth comes from sun. Without sun we wouldn't have rivers (no rains), we wouldn't have wind (let alone oil or coal) etc. We would only have geothermal and seismic power.
Direct sun radiation conversion (via collectors or photovoltaic) is not very popular yet. But indirectly sun is the main source of earths energy.