Thermodynamics Problems
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The problems below are based on the principles and formulas discussed in the coursework- In this assignment we will use metric units; here is a
short summary of these units:
Force is measured in Newtons (N)
Volume is measured in cubic meters (m3)
Work and Energy are measured in Joules (J)
1 Joule = 1 Newton‘meter
Entropy is measured in Joules per Kelvin (J/K)
Be sure to show all of your work- If you write down the formula and the numbers you used I can give partial credit even if the answer is wrong- If you
just write the answer you will not get full credit and if the answer is wrong you will get no credit-
1- What type of measuring device relies on Zeroth's Law and how does it do this?
2- The temperature outside is 0 degrees Fahrenheit- What is the temperature in Kelvin?
3- An isolated system absorbs a heat transfer of 45J and performs 20 J of work- What is the internal energy of the system?
4- An isolated system contains some amount of internal energy. If 5 J of heat are transferred into the system, but the internal energy remains the
same, how much work must be done by the system?
5- How much work is done by a jet engine that exerts 245 N of force over a distance of 1 km?
6- A gas maintains a constant pressure of 45 mm while being heated- The resulting change in volume is 0-78 m3- What is the work done by the
gas?
7- The same gas in problem 6 had an internal energy of 85 J and a final volume of 2 m3- What is the enthalpy (H) of the gas?
8- The combustion process inside a jet engine creates 450 J of heat and does 110 J of work spinning a turbine shafl- What is the change in specific
enthalpy of the gas?
9- Through an irreversible process, object A transfers 96 J of heat to object 8. The resulting temperature of the system is 456 K- What is the entropy
of the system?