In a lab investigation, one group of students (group A) measures the speed of a 0.1kg car at 2.5m/s at the bottom of a hill. Another group of students (group B) measures the speed of the car at 3m/s at the bottom of the hill. Both cars started at the top of a hill that is 1m high. Calculate the potential and kinetic energies for each group's car.

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.