Ga projectile is shot directly away from earth's surface. neglect the rotation of the earth. what multiple of earth's radius re gives the radial distance (from the earth's center) the projectile reaches if (a) its initial speed is 0.216 of the escape speed from earth and (b) its initial kinetic energy is 0.216 of the kinetic energy required to escape earth? (give your answers as unitless numbers.) (c) what is the least initial mechanical energy required at launch if the projectile is to escape earth?

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.