Molecular Physics | Thermodynamics Answers

A student has designed his own thermometer with a temperature scale called S. Here

he has marked the freezing point of water as 30 °S and the boiling point of water as

150 °S. The S scale has 130 divisions.

(a) By drawing a suitable diagram, express the relation (mathematical equation)

between 𝑇𝐶 (temperature in Celsius) and 𝑇𝑆 (temperature in S)

(b) What reading will be shown in S scale when he measures the temperature of an

object at 60°C.

Carnot cycle. Consider a Carnot engine with a monoatomic ideal gas as an operating substance (i.e. the substance that undergoes the cyclic process to convert heat into work). One property of the ideal gas is that its internal energy is related only to its temperature, s.t. U=32nRTU=32nRT. The cyclic process is Show that you will get:

η=1− τc/τh

by getting the ratio of the total work done over the total amount of heat entering the system.

6. A house wall consists of a 10 cm thick layer of brick (𝜅 = 0.68 𝑊𝑚−1𝐾

−1

), a 15 cm 

thick layer of fiberglass insulation (𝜅 = 0.038 𝑊𝑚−1𝐾

−1

), and a 1 cm thick layer of 

gypsum board (𝜅 = 0.48 𝑊𝑚−1𝐾

−1

). The interior surface temperature is 22℃ and exterior 

surface temperature is 5 ℃.

(a) What is the overall R-value of this wall?

(b) What is the heat flux through this wall?

The best leaper in the animal kingdom is the puma, which can jump to a height of 3.7 m when leaving the ground at an angle of 45°. With what speed must the animal leave the ground to reach that height?

If the rail has a cross sectional area of 30cm2, the force of compression on the railway will be

A heat pump cycle delivers energy by heat transfer to a dwelling at a rate of 11.7 kW. The coefficient of performance of the cycle is 2.8. Evaluating electricity at $0.10 per kW ⋅ h, determine the cost of electricity during the heating season when the heat pump operates for 1800 hours.

Steam enters a nozzle at pressure of 6 bar and 2000c with enthalpy 2850 kJ/kg and leaves at a pressure of 1.5 bar. The initial velocity of steam is 50m/s and the exit velocity from nozzle is 650 m/s. The mass flow rate through the nozzle is 1500kg/h, the heat loss from the nozzle is 12000 kJ/hr. Determine the final enthalpy of steam

Air flows steadily through an engine at a constant temperature of 400k. Find the work per kilogram if the exit pressure is one-third the inlet pressure and the inlet pressure is 207 KPa. Assume that the kinetic energy and potential energy variation are negligible.

1. During a steady flow process, the pressure of the working substance drops from 400 to 40 psia, the speed increase s from 300 to 1100 fps, the internal energy of the open system decreases 30 Btu/lb, and specific volume increases from 1.2 to 9 ft^3/lb. no heat is transferred. Sketch the energy diagram. Determine the work per lb. Is it done Or by substance? Determine the work in hp for 11 lb per min.( 1 hp = 42.4 Btu/min).

Water is flowing at a rate of 100 L/s in a 20 cm diameter pipe. How fast is the water flowing in m/s?