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
Answer:
D is the answer I think (0 w 0 )
Explanation:
To calculate the specific heat capacity of an object or substance, we can use the formula
c = E / m△T
Where
c as the specific heat capacity,
E as the energy applied (assume no heat loss to surroundings),
m as mass and
△T as the energy change.
Now just substitute the numbers given into the equation.
c = 2000 / 2 x 5
c = 2000/ 10
c = 200
Therefore we can conclude that the specific heat capacity of the block is 200 Jkg^-1°C^-1
Answer:
B.
Explanation:
According to CDC, if you’re doing moderate-intensity activity, you can talk but not sing during the activity.
Well the chocolate bar may melt at the heat of the machine but why is there a chocolate bar there in the first place is my question xD
