Two blocks are connected by a rope, as shown below. The masses of the blocks are 10kg for the lower block and 5kg for the upper block . An upward applied force of magnitude F acts on the upper block. If F = 450N which of the following predictions about the acceleration of the two block system is correct? 1) The system accelerates downward with a magnitude 2g
2) The system accelerates downward with a magnitude 3g
3) The system accelerates upward with a magnitude 2g
4) The system accelerates upward with a magnitude 3g

An observer that stands still as the electron moves by him, will observe

Tafari worked one summer on a ship that set weather buoys in the ocean. he watched how one of the buoys moved in the water. describe which parts of the wave would cause the buoy to bob up and down. which wave property determined how fast the buoys bobbed in the water? he observed that when the wind blew harder, the ocean waves were larger, and the buoys moved away from the ship. what effect, if any, did the waves have on how far the buoys moved? explain your answer.

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.