Suppose that one weekend day a hiker exerts 200 Watts of power while ascending 300 meters on a steep trail without a pack. The hiker repeats this trip the following weekend but is carrying an additional 10 kilograms in a pack. How much longer should the hiker expect her ascent to take assuming her power output remains the same.
Recall that it takes approximately 10 joules to raise 1 kilogram 1 meter.