Question

which type of engine uses a power piston and a displacer piston?

○ a. steam engine
○ b. deutz engine
○ c. stirling engine
○ d. wankel engine

Explanation:

A Stirling engine operates with a power piston (for work output) and a displacer piston (to move working fluid between hot and cold spaces). Steam engines use different piston mechanisms for steam expansion, Deutz engines are internal combustion with typical pistons, and Wankel engines use a rotor, not two pistons like this.

Answer:

c. Stirling engine