Halliday, Resnick & Walker — Temperature, Heat, and the First Law of Thermodynamics: Problem 49

Figure 18.19 represents a closed cycle for a gas (the figure is not drawn to scale). The change in the internal energy of the gas as it moves from \( a \) to \( c \) along the path \( abc \) is \( -200\text{ J} \). As it moves from \( c \) to \( d \), \( 180\text{ J} \) must be transferred to it as heat. An additional transfer of \( 80\text{ J} \) to it as heat is needed as it moves from \( d \) to \( a \). How much work is done on the gas as it moves from \( c \) to \( d \)?