Molecular Physics | Thermodynamics Answers

1. On the Rankine temperature scale, which is sometimes used in engineering applications, the ice point is at 491.67 °R and the stem point is at 671.67 °R.

a.) Determine the relationship between the Rankine and Fahrenheit temperature scales.

b.) A healthy person has an oral temperature of 98.67 °F. Calculate what would this reading be on the Rankine temperature scale.

2. Two identical thermometers made of Pyrex glass contain, respectively, identical volumes of mercury and methyl alcohol. If the expansion of the glass is taken into account, calculate how many times greater is the distance between the degree marks of the methyl alcohol thermometer than the distance on the mercury thermometer.

A steam enters a boiler at 3.42 bar, specific volume of 0.567 m3/kg, specific internal energy of

1892kJ/kg at velocity of 5 m/s. At rate 3 kg/s, th steam exit with 755 kN/m2, specific volume

of 0.892 m3/kg,specific internal energy of 2014 kJ/kg and velocity of 35 m/s. The boiler's exit

is 2m higher than the entrance. Calculate the heat transfer in kW and state either it is into or

out of the system.

An air occupies in the tank with pressure and volume of 6.5 bar and 0.37 m3 at 48 °C.After

an isobaric expansion, the volume increased to 0.42 m3. Determine the final temperature in

unit °C and the mass of the gas.

A piston of radins R=20 cm is free to move without friction inside a vertical cylinder filled with water and having the same diameter as that of the piston. The piston that floats at the surface of water is traversed by a hollow vertical straw with a radius r =1 cm Caleulate the height of water in the straw if the piston weighs 1250 N. P-1000 Ka/m3

A combustion engine is to be used for gas compressor in the cylinder. Initial expansion,internal energy is 1000kJ/kg. At the end of the process, the internal energy has been decreased by 700kJ/kg. Calculate the heat transfer if the work done to the system is

0.2MJ/kg and state either the heat is rejected or transferred to the system.

Calculate the heat required to convert 2kg of ice at -12°c to steam at 100°c. L for ice= 336000j/kg, L for steam= 2260000. C for ice = 2100j/kg/k

With a 3-fold increase in the radius of the circular orbit of an artificial Earth

satellite, the period of its rotation increases by 6 times. How many times will

the satellite's orbital speed change?

The surface area of a person is 1.9m² and the skin temperature is 31°C. What are the rates of heat transfer through the skin when there is almost no blood flow to the skin and when there is maximum blood flow to the skin?

A closed vessel made of brass 4mm thick ,has a surface area 0•2m^2 and contains 5×10^-3m^3 of hot water.calculate the Temperature difference which exists between the inside and outside surfaces of the brass vessel if the water is cooling at 1kelvin per second?

Calculate the mean free path of a gas of randomly-moving hard spheres of 2 nanometer radius, when the density of spheres is 3.00 x 10¹⁹ per cubic meter.

• A. 1.17 × 10^-4 m
•  B. 9.76 × 10^-5 m
•  C. 4.70 × 10^-4 m
•  D. 1.88 × 10^-3 m
•  E. None of the above.