A 55 kg engineer leaves her office on the 33rd floor of a skyscraper and takes an elevator to the 59th floor. Later she descends to street level. If the engineer takes her office as the zero for potential energy and if the distance from one floor to the next is 3.5 m, what is the engineer’s potential energy (a) in her office, (b) on the 59th floor, and (c) at street level?
2 answers
To quote one of our very good math and science tutors: “You will find here at Jiskha that long series of questions, posted with no evidence of effort or thought by the person posting, will not be answered. We will gladly respond to your future questions in which your thoughts are included.”
mass m = 55 kg
Distance from one floor to the next h =3.5 m
(a). Potential energy in her office P= mg * 0 = 0 J
Since her office as the zero potential energy
(b). Potential energy on the 59 th floor = mg ( 59 th floor -33 floor )
= mg * 26 floors
= mg * 26 h
= 55*9.8 * 26 * 3.5
= 49049 J
(c). Potential energy at strret level = mg ( 0 thfloor - 33 floor )
= mg * -33 floors
= mg * -33h
= 55*9.8 * -33 * 3.5
= - 62254.5J
Distance from one floor to the next h =3.5 m
(a). Potential energy in her office P= mg * 0 = 0 J
Since her office as the zero potential energy
(b). Potential energy on the 59 th floor = mg ( 59 th floor -33 floor )
= mg * 26 floors
= mg * 26 h
= 55*9.8 * 26 * 3.5
= 49049 J
(c). Potential energy at strret level = mg ( 0 thfloor - 33 floor )
= mg * -33 floors
= mg * -33h
= 55*9.8 * -33 * 3.5
= - 62254.5J
5 answers