Steam turbines: definition of blading efficiency (diagram efficiency) The ratio of the work done on the blades to the energy supplied to the blades is called: Choose the correct option.

Concept
Energy supplied to the blades (from the nozzle) appears mainly as kinetic energy of steam jets. The fraction of that energy actually converted into work on the rotor is the blading (diagram) efficiency.

Why others are wrong
Nozzle efficiency compares actual and isentropic jet velocities in the nozzle.Stage efficiency combines nozzle and blade effects.Mechanical efficiency accounts for mechanical losses between rotor and output shaft.

Final Answer
Blading efficiency