Answer: 80J
Explanation:
According to the first principle of thermodynamics:
<em>"Energy is not created, nor destroyed, but it is conserved." </em>
Then this priciple (also called Law) relates the work and the transferred heat exchanged in a system through the internal energy 
, which is neither created nor destroyed, it is only transformed. So, in this especific case of the compressed gas:
(1)
Where:
is the variation in the internal (thermal) energy of the system (the value we want to find)
is the heat transferred out of the gas (that is why it is negative)
is the work is done on the gas (as the gas is compressed, the work done on the gas must be considered positive )
On the other hand, the work done on the gas is given by:
(2)
Where:
is the constant pressure of the gas
is the variation in volume of the gas
In this case the initial volume is 
and the final volume is 
.
This means:
(3)
Substituting (3) in (2):
(4)
(5)
Substituting (5) in (1):
(6)
Finally:
This is the change in thermal energy in the compression process.
Answer:
Work done on an object is equal to
FDcos(angle).
So, naturally, if you lift a book from the floor on top of the table you do work on it since you are applying a force through a distance.
However, I often see the example of carrying a book through a horizontal distance is not work. The reasoning given is this: The force you apply is in the vertical distance, countering gravity and thus not in the direction of motion.
But surely you must be applying a force (and thus work) in the horizontal direction as the book would stop due to air friction if not for your fingers?
Is applying a force through a distance only work if causes an acceleration? That wouldn't make sense in my mind. If you are dragging a sled through snow, you are still doing work on it, since the force is in the direction of motion. This goes even if velocity is constant due to friction.
Explanation:
Answer:
age of the site is 15411.75 years old
Explanation:
Given data
plant or animal dies = 14C
time period = 5730 year
carbon = 15.5%
to find out
age (in years) of the ancient site
solution
we know that Final value = Initial value × 
here n is half life passed
so for 15.5%
15.5% = 100% of
0.155 = 1 ×
now take log both side
log 0.155 = log
n = log 0.155 / log 0.5
n = 2.68966
we know here 5730 years in half life
so for 2.68966 half-lives = 2.68966 × 5730 = 15411.7518
age of the site is 15411.75 years old
= Heat released to cold reservoir
= Heat released to hot reservoir
= maximum amount of work
= temperature of cold reservoir
= temperature of hot reservoir
we know that
eq-1
maximum work is given as
= -
using eq-1
= 
-
