Ham Radio General Class Practice Test

What is one way that RF energy can affect human body tissue?

1. It heats body tissue

2. It causes radiation poisoning

3. It causes the blood count to reach a dangerously low level

4. It cools body tissue

The correct answer is: It heats body tissue

The correct answer is that RF (radio frequency) energy can heat body tissue. This phenomenon occurs because RF energy is a type of electromagnetic radiation, and when it interacts with biological tissue, it can cause molecules to vibrate and generate heat. This is similar to how microwave ovens work, where microwaves excite water molecules in food, warming it up. When RF energy levels are sufficiently high, this heating effect can lead to thermal injuries if the tissue is exposed for prolonged periods. The extent of this heating depends on several factors, including the intensity of the RF exposure, the duration, and the specific frequency of the RF energy. In contrast, the other options do not accurately describe the effects of RF energy on human body tissue. While radiation can indeed cause harm, RF energy at non-ionizing levels does not cause radiation poisoning. Similarly, RF exposure is not linked to causing low blood counts or cooling tissue. Instead, the primary concern regarding RF exposure in the context of safety guidelines focuses on the potential for thermal effects leading to tissue heating.