A weightless piston divides a thermally insulated cylinder into two pa...
As the expansion is against zero pressure, so no work is done. Now, for given mass of gas,
PV = P
1V
1= P
1 x 4V
∴ P
1 = P/4 is the pressure of gas after expansion.
In the second process, compression is adiabatic, so
Change in internal energy = work done in adiabatic compression.
= 8P
1V = 2PV
= 2 * 2 * 10
5 * 10
-3 = 400J
Further,
∴
= 12.05
∴ Final temperature = T
1 + (T
2 - T
2)
= 300 + 12.05 = 312.05 K
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A weightless piston divides a thermally insulated cylinder into two pa...
To solve this problem, we need to consider the fact that the process is adiabatic, meaning there is no heat exchange with the surroundings. Therefore, the change in internal energy of the gas is equal to the work done on or by the gas.
First, let's calculate the initial and final volumes of the gas.
Initial volume of the gas (V1) = 1 litre
Final volume of the gas (V2) = 3V + V = 4V
Next, let's calculate the work done on the gas when it expands.
Work done on the gas (W) = P * (V2 - V1)
= 2 atm * (4V - 1 litre)
Now, we need to find the value of V. To do this, we can use the ideal gas law.
PV = nRT
Since the gas is at room temperature, we can assume it is at 298 K.
Substituting the given values, we have:
2 atm * V = 2 moles * 0.0821 L.atm/(mol.K) * 298 K
V = 2 * 0.0821 * 298 / 2
V = 48.822 L
Now, we can substitute the value of V in the equation for work done:
W = 2 atm * (4 * 48.822 L - 1 litre)
W = 2 atm * (195.288 L - 1 litre)
W = 2 atm * 194.288 L
Finally, we can calculate the increase in internal energy (ΔU) using the first law of thermodynamics:
ΔU = W
Substituting the value of W, we have:
ΔU = 2 atm * 194.288 L
To convert this to Joules, we need to multiply by the conversion factor:
ΔU = 2 atm * 194.288 L * 101.325 J/(L.atm)
ΔU = 39361.56 J
Therefore, the increase in internal energy of the gas in this process is 39361.56 Joules.