The efficiency of a Carnot engine is calculated using the formula: η=1−‌
T‌sink ‌
T‌source ‌
Given that the absolute temperature of the source ( T‌source ‌ ) is 25% more than that of the sink ( T‌sink ‌ ), we can express this relationship as: T‌source ‌=T‌sink ‌+‌
25×T‌sink ‌
100
Simplifying, this becomes: T‌source ‌=1.25×T‌sink ‌ Substituting into the efficiency equation, we have: η=(1−‌
T‌sink ‌
1.25×T‌sink ‌
)×100% This simplifies to: ‌η=(1−‌
1
1.25
)×100% ‌η=(1−0.8)×100% ‌η=0.2×100% Thus, the efficiency of the Carnot engine is: η=20%