The correct answer is 42
\(Q = msΔT\)
\(\frac{dQ}{dt} = (\frac{dm }{dt})_{water}\)
\( SΔT = (\frac{dm}{dt})_{oil}C\)
\(⇒ 2 × 4.2 × 10³ × 40\)
\(= (\frac{dm}{dt})_{oil} × 8 × 10^6\)
\(⇒ (\frac{dm}{dt})_{oil} = \frac{8 × 4.2 × 10^4}{8 × 10^6} kg/minute\)
= 42 g/minute
In 1st case, Carnot engine operates between temperatures 300 K and 100 K. In 2nd case, as shown in the figure, a combination of two engines is used. The efficiency of this combination (in 2nd case) will be:
From the second law of thermodynamics, two important results are derived where the conclusions are taken together to constitute Carnot’s theorem. It may be stated in the following forms.