A sound wave with amplitude xo is measured by an observer to have an intensity of I0 when the observer is standing 4.0 meters from the source. Which best describes the amplitude of a sound wave and distance from the source where it will be measured with an intensity of 16Io? Increase the amplitude to 8xo and stand 2 meters from the source. Increase the amplitude to 4xo and stand 10 meters from the source. Increase the amplitude to 2xo and stand 2 meters from the source. Increase the amplitude to 4xo and stand 8 meters from the source.

Antireflective coatings on solar cells are often made by applying a thin film of silicon nitride (sinx), which has an index of refractive of 1.2, on the top of the silicon solar cell, which has a refractive index of about 3.5. however, the sun emits radiation of various wavelengths which the solar cell absorbs, and the antireflective coating can only absolutely minimize the reflection of one of these wavelengths. the coating thickness is chosen to reduce the reflection of green/yellow light (e = 2.2 ev), which is the most intense color in the solar spectrum (shown below). which of the following coatings would minimize reflection of green/yellow light? the answer is 820 nm how? what is the angular width of the central maximum of an electron traveling at 2 x 108 m/s going through a single slit of width 1 mm.