How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

To determine the true power being absorbed by the load (or radiated by an antenna), you simply subtract the reflected power from the forward power. In this scenario, the directional wattmeter indicates 100 watts heading toward the load and 25 watts bouncing back. The calculation is 100 W - 25 W = 75 W. The remaining 75 watts is the power that the load successfully absorbed and dissipated as heat or radiated as RF energy.