Molecular Physics | Thermodynamics Answers

There are expanded isothermally 3 lb/sec of NH, from saturated vapor to the state of 10 psia, 100°F. Determine (a) Q, (b)W (nonflow), (c) W (steady flow with ∆K=0), (d) ∆G, (e) the unavailable part of Q for t= 60°F. See Item B 33.

An adiabatic vessel contains steam at 1025 psia, 750°F. A valve is opened slowly permitting an outflow of steam; it is closed quickly when the steam remaining in the vessel becomes saturated vapor. What fractional part of the original steam remains? Assume that this part underwent a reversible adiabatic expansion.

Say & lb/sec of CO₂ gas are com .2 H pressed polytropically (pV¹² = C) from Pi =. 15 psia, ₁ 140°F to 1₂ = 440°F. As suming ideal gas action, find P2, W, Q, AS (a) as a nonflow process, (b) as a steady flow process where AP = 0, AK = 0.

Confine 1 lb of wet steam at 500°F and with an enthalpy of 800 Btu in a rigid container. Heat is applied until the steam becomes saturated. Determine (a) the initial pressure p₁, (b) quality x₁, (c) volume v₁, (d) the final pressure p2; and for the process, (e) W, (f) O.

Q 5. A 5 kg of ice cube at −10℃ is mixed with 0.1 kg of water at 80 ℃. There is no heat 

loss to the surrounding. The specific heat capacity of ice is 2.22 𝑘𝐽𝐾

−1𝑘𝑔−1

,The specific 

heat capacity of water is 4.187 𝑘𝐽𝐾

−1𝑘𝑔−1

. The specific latent heat of fusion of ice is 

333 𝑘𝐽 𝑘𝑔−1

.

(a) What is the final physical state of the mixture? (Gas, Liquid or Solid?)

Justify your answer using suitable calculations 

(b) What is the final temperature of the mixture?

A certain ideal gas has a constant R = 38.9 ft-lb/lb-°R with k = 1.4. (a) if 3 lb of this gas undergoes a reversible nonflow.constant volume process from P, = 20 psia, 140°F to 740°F find: • the change in internal energy in Btu. . the change in enthalpy in Btu. • the heat in Btu. . the work in Btu. b. If the process in (a) is had been steady flow with AP=O. AK = 0, find: • the work in Btu. . the change in entropy in Btu/R.

The internal energy of the certain substance is given by the following equation

u = 3.56 pv + 184

where u is given in kJ/kg, p is in kPa and v is in m3

/kg.

A system composed of 3 kg of this substance expands from an initial pressure of 500

kPa and volume of 0.22 m3

to final pressure 100 kPa in a process in which pressure and

volume are related by pv1.2 = Constant. If expansion is quasi-static, find Q, ∆U and W

for the process.

9.The electric motor of a model train accelerates the train from rest to 0.620m/s in 21s. The 

total mass of the train is 875g. Find the average power delivered to the train during the 

acceleration? 

A 734 kg car is stuck on a road, 990 kg is traveling at 12 m/s to the east collides with the rear side of the car which is stuck on the road. In your role as an expert witness, you inspect the scene and determine that, after the collision, the 734 kg car slides on the road at 5 m/s in a direction 30 degrees north of east. Ignoring the effects of friction during the collision, calculate the magnitude of the velocity (in m/s) of the 990 kg car after the collision

A 5 kg of ice cube at -10°C is mixed with 0.1 kg of water at 80 °C. There is no heat loss to the surrounding. The specific heat capacity of ice is 2.22 kJK-'kg-1,The specific heat capacity of water is 4.187 kJK-'kg-! . The specific latent heat of fusion of ice is 333 kJ kg-1. (a) What is the final physical state of the mixture?