The pressure at the outlet from the moving blades is the same as the pressure at the inlet to the moving blades in a/an __________ turbine.

In an impulse turbine, the pressure at the outlet from the moving blades is indeed the same as the pressure at the inlet to the moving blades. This is a fundamental characteristic of impulse turbines, which operate on the principle of converting the kinetic energy of a high-speed jet of fluid into mechanical energy.

In impulse turbines, the working fluid (usually steam or water) is directed onto the turbine blades through nozzles, which increases the fluid's velocity. The blades are designed to harness this kinetic energy. As the fluid passes over the blades, there is a conversion of the dynamic pressure (from the velocity of the fluid) into mechanical energy, while maintaining the same static pressure at both the inlet and outlet. This means that the pressure drop occurs in the nozzle where the fluid velocity increases, but between the inlet and outlet of the moving blades, the pressure remains constant.

This design contrasts with reaction turbines, where the pressure changes across the blades, indicating that some pressure energy is converted into kinetic energy as the fluid expands through the rotor blades. In back pressure turbines, the outlet pressure is intentionally kept high to ensure that the steam does useful work before being exhausted, which is different from the principles governing impulse turbines.

Therefore, the essential nature of impulse turbines is