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Physics, 16.07.2021 02:00 yyyyyy290

Electromagnetic Wave PenetrationRadio waves and mircowaves are used in therapy to provide "deep heating" of tissue because the waves penetrate beneth the surface of the body and deposit energy. We define the penetration depth as the depth at which the wave intensity has decreased to 37% of its value at the surface. The penetration depth is 15cm for 27MHz radio waves. For radio frequencies such as this, the penetration depth is proportional to (sqrt of lambda), which is the square root of the wavelength. What is the wavelength of 27 MHz radio waves? A. 11 m. B. 9.0 m. C. 0.011 m. D. 0.009 m. If the frequency of the radio waves is increased, the depth of penetration:.A. Increases. B. Does not change. C. Decreases. 3. For 27 MHzMHz radio waves, the wave intensity has been reduced by a factor of 3 at a depth of approximately 15 cmcm. At this point in the tissue, the electric field amplitude has decreased by a factor of:.A. 9 77. B. 3√3. C. 3. D. √3.

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Electromagnetic Wave PenetrationRadio waves and mircowaves are used in therapy to provide "deep heat...
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