Respuesta :
Explanation:
The given data is as follows.
Initial temperature ([tex]T_{1}[/tex]) = [tex]40^{o}F[/tex] = 499.67R
Initial pressure ([tex]P_{1}[/tex]) = 16.8 Psi
Volume (V) = 5 [tex]ft^{3}[/tex]
Work done = 4 Btu
Final temperature ([tex]T_{2}[/tex]) = 90 F
So, R of [tex]O_{2}[/tex] = 0.3353 Psi ft^{3}/lbm R
Therefore, we will calculate the mass of oxygen as follows.
M = [tex]\frac{PV}{RT}[/tex]
= [tex]\frac{16.8 \times 5}{0.3353 \times 499.67}[/tex]
= 0.50137 lbm
Therefore, mass of oxygen is 0.50137 lbm.
Now, we will calculate the change in internal energy as follows.
[tex]\Delta U = mC_{v} [T_{2} - T_{1}][/tex]
= [tex]0.50137 \times 0.157 \times (90 - 40)[/tex]
= 3.936 BTU
Relation between heat energy and internal energy is as follows.
[tex]\Delta Q = \Delta u + W.d[/tex]
= [tex]3.936 + (-4)[/tex]
= -0.0642 BTU
Therefore, amount of heat transfer in BTU is 0.0642 BTU.
