Q. Hydraulic engineers often use, as a unit of volume of water, the "acre-foot", defined as the volume of water that will cover 1 acre of land to a depth of 1 ft. A severe thunderstorm dumps 2.0 in. of rain in 30 min on a town of area 35 km2. What volume of water, in acre-feet, fell on the town?
Q. An electron with an initial speed of 5.50×105 m/s is brought to rest by an electric field. What was the potential difference that stopped the electron?