JEE Mains · Physics · STD 11 - 11. thermodynamics
A Carnot engine \((\mathrm{E})\) is working between two temperatures 473 K and 273 K . In a new system two engines - engine \(E_1\) works between 473 K to 373 K and engine \(E_2\) works between 373 K to 273 K .If \(\eta_{12}, \eta_1\) and \(\eta_2\) are the efficiencies of the engines \(E, E_1\) and \(E_2\), respectively, then
- A \(\eta_{12}=\eta_1 \eta_2\)
- B \(\eta_{12} \geq \eta_1+\eta_2\)
- C \(\eta_{12}=\eta_1+\eta_2\)
- D \(\eta_{12} \lt \eta_1+\eta_2\)
Answer & Solution
Correct Answer
(D) \(\eta_{12} \lt \eta_1+\eta_2\)
Step-by-step Solution
Detailed explanation
Efficiencies of a carnot engine \(\eta=1-\frac{T_{\text {sink }}}{T_{\text {source }}}\)…
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