A Carnot engine functions between a hot reservoir at \( T_H = 600 \, \text{K} \) and a cold reservoir at \( T_C = 300 \, \text{K} \). It takes in \( Q_H = 900 \, \text{J} \) of heat from the hot reservoir. The objective is to calculate the work \( W \) output by the engine.
The efficiency \( \eta \) for a Carnot engine is defined by the equation:
\(\eta = 1 - \frac{T_C}{T_H}\)
Plugging in the provided temperatures yields:
\(\eta = 1 - \frac{300}{600} = 1 - 0.5 = 0.5\)
The efficiency can also be represented as the ratio of work done to heat absorbed:
\(\eta = \frac{W}{Q_H}\)
Solving for work \( W \):
\(W = \eta \times Q_H\)
Substituting the known values:
\(W = 0.5 \times 900 \, \text{J} = 450 \, \text{J}\)
Consequently, the work performed by the Carnot engine is 450 J, aligning with the second option previously indicated.