15.2 The First Law of Thermodynamics and Some Simple Processes

In the figure, how much work is done by the system in process AB?

1. 4.5 × 10³ J
2. 6.0 × 10³ J
3. 6.9 × 10³ J
4. 7.8 × 10³ J

A thermodynamic process begins at 1.2 × 10⁶ N/m² and 5 L. The state then changes to 1.2 × 10⁶ N/m² and 2 L. Next it becomes 2.2 × 10⁶ N/m² and 2 L. The next change is 2.2 × 10⁶ N/m² and 5 L. Finally, the system ends at 1.0 × 10⁶ N/m² and 5 L.

On the figure, this process is best described by

1. EFCDB
2. DEFCD
3. CFABC
4. CFABD

In the figure, which of the following cycles has the greatest net work output?

1. ABDA
2. BCDB
3. (a) and (b) are equal
4. ADCBA

A car tire contains $0 . \text{0380} m^{3}$ of nitrogen at a gauge pressure of $2 . \text{20} \times \text{10}^{5} \text{ N}/\text{m}^{2}$ (about 32 psi). How much more internal energy does this gas have than the same volume has at zero gauge pressure (which is equivalent to normal atmospheric pressure)? (Use $E_{\text{int}} = \frac{5}{2} N k T$ for the internal energy of nitrogen, a diatomic gas.)

Steam to drive an old-fashioned steam locomotive is supplied at a constant gauge pressure of $1 . \text{75} \times \text{10}^{6} \text{ N}/\text{m}^{2}$ (about 250 psi) to a piston with a 0.200-m radius. (a) By calculating $P \Delta V$, find the work done by the steam when the piston moves 0.800 m. Note that this is the net work output, since gauge pressure is used. (b) Now find the amount of work by calculating the force exerted times the distance traveled. Is the…

What is wrong with the claim that a cyclical heat engine does 4.00 kJ of work on an input of 24.0 kJ of heat transfer while 16.0 kJ of heat transfers to the environment?