Reference no: EM131727389
Maximum Efficiency of an Engine
Engineers are always searching for ways to make heat engines more efficient. The ideal heat engine would convert all the heat absorbed into work. According to the Second Law of Thermodynamics, however, no heat engine can have 100% efficiency. In 1824, the French engineer Sadi Carnot (1796-1832) determined the maximum possible efficiency of a heat engine allowed by the second law. This maximum possible efficiency is called the Carnot efficiency, eCarnot. The Carnot efficiency depends only on the temperatures of the hot and cold baths, sometimes called reservoirs. The Carnot efficiency is given by eCarnot = 1 - Tcold / Thot
where THot is the temperature of the hot reservoir and TCold is the temperature of the cold reservoir. There is one special consideration, however. The temperature must be expressed using the Kelvin temperature scale. The Kelvin scale is named for the British physicist Lord Kelvin (1824-1907). The Kelvin scale is related to the Celsius scale through the relationship
Tk - Tc + 273.15
where TK is the temperature in kelvins (K) and TC is the temperature in degrees celcius (°C).
1. For the heat engine used in this experiment, the temperatures of the hot bath and the cold bath were
THot = 80 °C and TCold = 0 °C, respectively. Calculate THot and TCold in kelvins.
2. Calculate the Carnot efficiency for this heat engine.