Charter pushes a bag full of basketball jerseys across the gym floor then he pulled with a constant force of 21 newtons if he pushes the bag 9 meters in 3 seconds how much power does he usea. 3 wattsb. 7 wattsc. 27 wattsd. 63 wattse. 189 watts

Free runners jump long distances and land on the ground or a wall. how do they apply newton’s second law to lessen the force of impact?

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

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.