Answer:
the first one is D
Explanation:
so if the others u put are right the the second would be c
Memorize this and you'll be able to do ALL of these: <em>1 kg = 1,000 g</em>
So if you have some grams, divide the number by 1,000 to get kilograms.
1,000 g = 1.000 kg
500 g = 0.500 kg
100 g = 0.100 kg
50 g = 0.050 kg
20 g = 0.020 kg
10 g = 0.010 kg
Answer:
Index of expansion: 4.93
Δu = -340.8 kJ/kg
q = 232.2 kJ/kg
Explanation:
The index of expansion is the relationship of pressures:
pi/pf
The ideal gas equation:
p1*v1/T1 = p2*v2/T2
p2 = p1*v1*T2/(T2*v2)
500 C = 773 K
20 C = 293 K
p2 = 35*0.1*773/(293*1.3) = 7.1 bar
The index of expansion then is 35/7.1 = 4.93
The variation of specific internal energy is:
Δu = Cv * Δt
Δu = 0.71 * (20 - 500) = -340.8 kJ/kg
The first law of thermodynamics
q = l + Δu
The work will be the expansion work
l = p2*v2 - p1*v1
35 bar = 3500000 Pa
7.1 bar = 710000 Pa
q = p2*v2 - p1*v1 + Δu
q = 710000*1.3 - 3500000*0.1 - 340800 = 232200 J/kg = 232.2 kJ/kg