Question

a 40 kilogramstudent runs up a staircase to a floor that is 5.0 meters higher than her starting point in 7.0 seconds. the student's power output is

Answer 1

When she reaches the top, she has more potential energy than she had at the bottom.

         Potential energy = (mass) x (gravity) x (height)

                                     = (40 kg) x (9.8 m/s²) x (5 m)

                                     =    1,960 more joules .

         Power = (energy) / (time)

                     = (1,960 joules) / (7 seconds)

                     =         280 watts

                    (about 0.375 horsepower)