Final answer:
True, throttling a compressor reduces its volumetric efficiency because it diminishes the mass flow rate, leading to less effective filling of the compressor volume. Similarly, in simple machines, efficiency is always less than 100 percent due to energy loss as heat from friction.
Step-by-step explanation:
Throttling a compressor does indeed reduce the volumetric efficiency. Volumetric efficiency is a measure of the effectiveness with which the compressor fills its displacement volume with air or gas. When a compressor is throttled, the mass flow rate of the air or gas through the compressor is reduced, which means that the available volume is not filled as effectively with the working fluid. This decreased mass flow rate results in a reduction of pressure at the outlet of the compressor for a given speed, leading to a decrease in volumetric efficiency.
As it relates to the concept of efficiency, it is also true that the efficiency of a simple machine is always less than 100 percent. This is because some portion of the input work is invariably converted into heat energy due to friction, reflecting the principle that energy transformations are not perfectly efficient.