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Question
Efficiency of a Carnot engine is large when ______.
Options
TH is large
Tc is low
TH – Tc is large
TH – Tc is small
Solution
Efficiency of a Carnot engine is large when TH – Tc is large.
Explanation:
`eta = 1 - T_C/T_H`
`eta = (T_H - T_C)/T_H`
Where:
- TH = Temperature of the hot reservoir (in Kelvin),
- TC = Temperature of the cold reservoir (in Kelvin).
Key Factors:
- Large TH: Increasing the temperature of the hot reservoir increases the efficiency because more heat energy is available for conversion into work.
- Small TC: Decreasing the temperature of the cold reservoir increases the efficiency as less energy is wasted in the form of heat rejected to the cold reservoir.
- Larger Temperature Difference (TH − TC): A greater temperature difference between the reservoirs enhances efficiency.
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