Communication with submerged submarines via radio waves is difficult because seawater is conductive and absorbs electromagnetic waves. penetration into the ocean is greater at longer wavelengths, so the united states has radio installations that transmit at 76 hz for submarine communications. what is the approximate wavelength of those extremely low-frequency waves?

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.