Bill is not only good at riding a bike with no hands, but he can also ride the bike with no hands and facing backwards while the bike goes forward. Bill is riding his bike in such a manner while playing catch with Betty who is stationary on the ground and facing Bill. Bill is on the bike (facing backwards toward Betty) and traveling away from Betty at a speed of 12.0 m/s when he throws a ball to Betty at a speed of 17.8 m/s relative to the bike. What is the velocity of the ball as measured by Betty

Aplane travels 1000 miles in 5 hours .what is the planes average speed?

Aspring has a natural length of 8 m. if a 12-n force is required to keep it stretched to a length of 10 m, how much work w is required to stretch it from 8 m to 16 m? (round your answer to two decimal places.)

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.