2. Thermodynamics

First Law — Quiz

Test your understanding of first law with 5 practice questions.

Practice Questions

Question 1

Which term in the general energy balance for an unsteady‐flow control volume represents the rate of energy accumulation within the control volume?

Question 2

A rigid, insulated tank contains 3 kg of an ideal gas with constant specific heat at constant volume $c_{v}=0.718\,$kJ/(kg·K). The gas is initially at 400 K and is heated with $Q=300\,$kJ added. Assuming no work is done, what is the final temperature $T_{2}$ of the gas?

Question 3

In the first law for a closed system undergoing a quasi‐static process, the boundary work associated with volume change is expressed by which integral?

Question 4

A compressor operates adiabatically on air at a mass flow rate $\dot m=0.1\,$kg/s, raising its specific enthalpy by $\Delta h=100\,$kJ/kg. Neglecting kinetic and potential energy changes, what is the required shaft power input $\dot W$?

Question 5

A steady‐flow adiabatic nozzle converts fluid enthalpy into kinetic energy. If velocity increases from $v_{1}=20\,$m/s to $v_{2}=200\,$m/s with negligible potential change, what is the specific enthalpy drop $\Delta h$?