A 80-kg person is running at 5 m/s is pushed by the wind for 20 seconds so that their velocity increases to 6 m/s. How much force does the wind apply to the runner?

Students in an introductory physics lab are performing an experiment with a parallel-plate capacitor made of two circular aluminum plates, each 11 cm in diameter, separated by 1.0 cm. how much charge can be added to each of the plates before a spark jumps between the two plates? for such flat electrodes, assume that value of 3×106n/c of the field causes a spark.