Microtherapy employs waves up to what frequency?

• A. Up to 2450 MHz
• B. 60 Hz
• C. 13-45 MHz
• D. 3000 MHz

Answer: (A)

Microwave-based heating in this modality uses electromagnetic waves in the microwave range, with the standard therapeutic frequency around 2.45 GHz. That makes 2450 MHz the upper limit typically used for microtherapy, chosen because this frequency provides effective tissue heating (dielectric heating) with manageable penetration and safety considerations. The other options fall outside this microwave range: 60 Hz is mains power frequency, not a therapeutic heating frequency; 13–45 MHz corresponds to shortwave diathermy, a different modality with a lower frequency; 3000 MHz (3 GHz) is higher than the common therapeutic microwave range. So the correct choice is 2450 MHz.