Một ô tô chuyển động từ A đến B với tốc độ 30m/s rồi lập tức quay lại A với tốc độ 20m/s. Tính tốc độ trung bình trên cả đoạn đi và về

When you drop a pebble from height a it reaches the ground with speed v if there is no air resistance. from what height should you drop it so it will reach the ground with three times the speed? (a) 9m (b) 3m (c) 6m (d) 18m

The solar panels used by mark function because of the photoelectric effect. light shines on the cells causing electrons to be ejected from the metal, which produces an electric current. at night on mars, no light will fall on the solar cells and no electric current will be generated. according to your notes, what type of light is typically needed to cause the photoelectric effect? a)visible b)ultraviolet c)infrared

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?