A gas is contained in a chamber such as that in Figure 15.5. Suppose the region outside the chamber is evacuated and the total mass of the block and the movable piston is 135 kg. When 2050 J of heat flows into the gas, the internal energy of the gas increases by 1735 J. What is the distance s through which the piston rises?
___________ m
figure 15.5: http://s29.photobucket.com/albums/c252/nevatrav/?action=view¤t=15_05.gif
2007-02-25 02:01:40 · 3 answers · asked by neverconsiderlifeonascale 1 in Science & Mathematics ➔ Physics
I would say that posters might consider answering when you give them one good reason that they rather than you should be doing you physics homework. It's actually a pretty easy problem and requires NO knowledge of the properties of gasses.
2007-02-25 02:07:09 · answer #1 · answered by Princess Marianna 1 · 0⤊ 19⤋
DATA
mass of piston = m = 135 kg
heat absorbed by system(gas) = Q = 2050 J
internal energy of system(gas) = E = 1735 J
acceleration due to gravity = g = 9.8 m/s^2
distance through which piston rises= h = ???
SOLUTION
According to first law of thermodynamics
Q = W + E
W =Q - E
W = 2050 - 1735
W = 315 J
Therefore
work done by system = work done by piston
W = mgh
W/(mg) = h
h = 315/(135 * 9.8)
h = 0.238095238 meters
2007-02-25 04:25:56 · answer #2 · answered by Sheeraz Ahmed 2 · 4⤊ 0⤋
use the first law of thermodynamics
(change in internal energy(U)=work done on system(W) + heat supplied to system(Q) )
+1735=W + 2050
W= -315
since work done on system is negative, it expands.therefore W=mgh=315
135(9.81)(h)=315
h=0.238m
2007-02-25 02:30:09 · answer #3 · answered by llcold 2 · 4⤊ 0⤋