An electric motor pumps 200 liter of water to a reservoir of height 6m in 2 s. Take g = 10 m/s?. Calculate the power developed by the motor. Take 1 liter of water = 1kg of water.

Emmy kicks a soccer ball up at an angle of 45° over a level field. she watches the ball's trajectory and notices that it lands, two seconds after being kicked, about 20 m away to the north. assume that air resistance is negligible, and plot the horizontal and vertical components of the ball's velocity as a function of time. consider only the time that the ball is in the air, after being kicked but before landing. take "north" and "up" as the positive ‑ and ‑directions, respectively, and use ≈10 m/s2 for the downward acceleration due to gravity.

Atemperature inversion can cause a warm air mass to move over a colder air mass. this traps the colder air mass and prevents surface air from rising. this may result in which of these? a) smog b) acid rain c) freezing rain d) a thunderstorm

To fully describe the photoelectric effect, scientists must consider which of the following to be quantized? o a. both light and matter o b. matter only o c. light only o d. neither light nor matter