If anyone can help me with either one of these physics problems, I would really appreciate any input. I am having problems with these two. Thanks a bunch :)
An electric scooter has a battery capable of supplying 120 Wh of energy. [Note that an energy of 1 Wh = (1 J/s)(3600 s) = 3600 J.] If frictional forces and other losses account for 57.5% of the energy usage, what change in altitude can a rider achieve when driving in hill terrain if the rider and scooter have a combined weight of 830 N (in m)?
While running, a person dissipates about 0.60 J of mechanical energy per step per kilogram of body mass. If a 52 kg person develops a power of 72 W during a race, how fast is the person running (in m/s)? (Assume a running step is 1.5 m long.) 2) 0.6J x 52kg = 31.2 J per step for that 52kg person
how many W in a J?....just use that ratio to find out how many Joules that person develops during a race and then divide that by 31.2J to find how many steps that person took then multiply by 1.5m (distance per step). | 