Is a reversible heat engine more efficient than an irreversible heat engine when operating between the same two thermal reservoirs?

Yes reversible heat engine is more efficient than irreversible heat engine

Explanation:

A reversible heat engine has more efficiency compared to an irreversible heat engine that is operating between the two same thermal reservoirs. Since the reversible process can do maximum work. Also reversible processes means any one of the process can be reversed without producing any effect on the systems as well as the surroundings, that is there is no loss of energy in case of a reversible process. While in case of irreversible process, there is loss of energy in the form of friction. Thus there is loss of energy in irreversible process, so its efficiency will be less than a reversible process.