A 20 kilogram object strikes the ground with 1830 Joules of kinetic energy after falling freely from rest. How much potential energy did the object have as it began to fall?

A110-pound person pulls herself up 4.0 feet. this took her 2.5 seconds. how much power was developed? 0.13 hp 0.32 hp 2.0 hp 3.1 hp

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.

For two variables in a direct proportion, what is the result of doubling one variable?