Under what condition, an ideal Carnot engine has 100% efficiency?

thermodynamics
cbse

#1

Efficiency of a Carnot engine is given by

where, ${ T }{ 2 }$ = temperature of sink and
and ${ T }
{ 1 }$ = temperature of sink source.
So n = 1 or 100%, ${ T }_{ 2 }$ = 0 K or heat is rejected into a sink at 0 K temperature.