(THERMODYNAMICS) A vertical cylinder fitted with a frictionless piston contains 1.5 kg of H2O initially at 100 °C, 400 kPa. If the volume of the system reaches 0.5 m3, the piston hits a set of stops and is restrained from further upward travel. The system is heated to 200 C. (Use saturated water tables, steam tables, and superheated tables as necessary)
a) If the piston reaches the stops, determine the temperature and pressure when the piston first touches but exerts no force on the stops. If the piston doesn’t reach the stops, find the final volume. Clearly show how you determined whether or not the piston reaches the stops.
b) Calculate the heat and work for the entire process.
c) Show the entire process on a T-v and P-v diagram including the saturation curve.
In: Mechanical Engineering
1) In accordance with the first law of thermodynamics, an 1250kW single effect absorption chiller with a COP of 0.86 will require a heat source of ______ kW and a heat rejection sink of ______ kW 2) If you were to change the absorption chiller specification to a double effect absorption chiller with a COP of 1.26, the heat source requirement would change to be _____ kW and a heat rejection sink of _______ kW would be needed in order to thermally power the cycle. 3) In your own words, describe what the difference between single and double effect absorption chillers in terms of their heat source requirements. Reference should be made to difference temperature requirements and a description on an installation that would be suitable for the deployment of each. Also include a summary of some of the common problems experienced with absorption chillers. 4) You have installed a large absorption chiller that provided a chilled water output of 4152 MWh in the last 12 months. The electric chiller that this machine replaced operated at an average COP of 4.36. How much electricity (MWh) did you save in the last 12 months?
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What is the difference between invention and innovation?
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Entropy flows out the system in form of a heat in an internally reversible process. What happened to the entropy of the system? Explain.
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1-Which pressure measuring device would you recommend to someone who needs to measure the pressure in a home gas cylinder before usage, and why?
2- Which pressure measuring device would you recommend to someone who needs to measure the pressure of a vacuum cleaner, and why?
In: Mechanical Engineering
Thermodynamics: It is not always possible or practical to measure a thermodynamic property directly. In the three following situations, select the measurements that are necessary to obtain the desired property. Use as few measurements as possible to get full credit. Justify your answers briefly.
1. You want to find the pressure inside a small tank of R134a refrigerant that you found in your lab. Assume the tank is entirely filled with refrigerant in liquid and vapor states. The system is at equilibrium. To this end you need to measure:
(a) Temperature inside the tank
(b) Total volume of refrigerant in the tank,
(c) Volume of liquid inside the bottle,
(d) Mass of liquid inside the tank.
2. You want to find the specific volume of an air-fuel mixture (modeled as air in a gaseous state) entering a gas turbine. To this end you need to measure:
(a) Temperature of the air-fuel mixture,
(b) Pressure of the air-fuel mixture,
(c) Mass flow rate of the air-fuel mixture,
(d) Speed of the air-fuel mixture.
3. Consider ice and liquid water in a glass sitting on your kitchen counter. You want to find the water level in the glass at the instant when the last piece of ice melts. The geometry of the glass is known. To this end you need to measure:
(a) Pressure in the kitchen,
(b) Temperature in the kitchen,
(c) Mass of ice,
(d) Mass of water (liquid and ice
In: Mechanical Engineering
stress= 2659.588351 psi , force = 522.209 psi/in^2 , area= 0.1963 in^2 , accuracy of load cell = 0.005 in , accuracy of calliper = 0.001 in ,
•What is the uncertainty in this stress calculation?
Determine which tool (load-cell or calipers) most affects stress calculation
*Could you please show all steps because i am going to do it in Excle
Thanks in advance
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A man sits in a boat, which is floating on the surface of a pond. He takes a rock from inside of the boat and throws it overboard into the pond, determine whether the level of the pond would rise, fall or remain unchanged? Support your answer with calculations
In: Mechanical Engineering
calculate the distance d from the center of the earth at which a particle experiences equal attractions from the earth and from the moon. The particle is restricted to the line through the centers of the earth and the moon. Justify the two solutions physically.
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A sensor outputs a voltage in the range of ±3mV. Your A/D samples at 1000 Hz, has an input range of ±10V, and has a 12-bit resolution. Design an active filter to amplify the sensor signal to fit at least 75% of the range of the A/D and filter anything above the Nyquist frequency. Justify your assumptions and show your work.
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Two materials, one with ε1 = 0.9 and the other with ε2 = 0.2 are available to use as filaments (light sources) for an incandescent lamp. Material 1 can be maintained at 2800 K, whereas material 2 can be maintained at 3000 K. Calculate the rate at which radiant energy is emitted per unit surface area (Watts/m2 ) from each of the two materials in the spectrum 0.4µm < λ< 0.8µm. Which material emits energy at the highest rate in this spectrum (assuming same surface area for both materials)?
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In: Mechanical Engineering
A 10 L adiabatic container contains 0.1 mol of air, at a temperature of 250 K. It is closed by a stopcock. Ambient air is at 300 K at a pressure of 1 bar. The stopcock is opened for a moment and a certain amount of air penetrates into the container. After thermal equilibrium is reached inside the container, the gas temperature is measured to be 350 K. 1) Assuming that the air behaves as an ideal gas, find the initial pressure in the container, the number of moles of air that penetrated in the container, the sum of the internal energy changes for the gas inside the container and the gas that entered it and the final pressure inside. 2) Find the enthalpy and entropy changes of the gas that is inside the container at the end of the process. Use κ = Cp,mol/CV,mol = 7/5 and Cp,mol − CV,mol = R.
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choose a type of electric motor and search the internet to find the specs and operational information such as horsepower rating available cost and common application
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Falls from Same Level and Falls from Heights
300-500 discussion, Please do not Copy write (will get a thumbs down)!!!!!!!!
Employers should be more concerned with falls to the same level than falls from heights?
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