Why is Carnot not irreversible?

[Abigale]

Hi,

I am thinking about the Carnot-Cycle-Process.
I know that a heat exchange is always irreversible.

But in the Carnot-Cycle, there is heating too.
Why is that kind of heating, in the Carnot-Process reversible?

Thx Abby

 

[guruji]

Heat exchange is always irreversible only for the processes which are not infinitesimally slow (or quasi-static or quasi-equilibruum) processes.

In Carnot-Cycle heating is done infinitesimally slowly, that's why it is reversible.