Thermodynamics I

Which of the following is an example of a closed system?

• A boiling pot with no lid

• A piston-cylinder with a fixed mass of gas

• An open water tank

• A river flowing into a dam

Which of the following is NOT an example of a control volume?

• Steam turbine

• Air compressor

• Sealed balloon

• Air diffuser

Which of the following is required to determine the state of water using a property table?

• Mass

• Specific heat

• Two independent intensive properties

• Volume only

What is the specific volume of a gas with P = 200 kPa, T = 500 K, and R = 0.287 kJ/kg·K?

• 0.500 m³/kg

• 0.718 m³/kg

• 0.358 m³/kg

• 0.143 m³/kg

Which statement about an ideal gas is correct?

• It follows the ideal gas equation only at low temperatures.

• It follows the ideal gas equation at all pressures and temperatures.

• It follows the ideal gas equation only in the superheated region.

• It follows the ideal gas equation only at high densities.

If the quality of a two-phase mixture is 0.6, it means:

• 60% of the mass is liquid

• 40% of the mass is vapor

• 60% of the mass is vapor

• The mixture is a saturated liquid

The first law of thermodynamics is a statement of:

• Entropy increase

• Conservation of energy

• Conservation of mass

• Heat transfer

A system undergoes a constant-volume process with a heat addition of 100 kJ. What is the change in internal energy?

• 100 kJ

• 0 kJ

• 50 kJ

• -100 kJ

Which of the following work expressions is correct for an isothermal process?

• W = PΔV

• W = mRT ln(V2/V1)

• W = ΔU

• W = Q - ΔU

Which of the following statements best describes a closed system?

• No mass and no energy cross the system boundary

• Energy crosses the boundary, but no mass transfer occurs

• Both mass and energy can cross the boundary

• The system exchanges work but not heat