An elevator and the people inside have a combined mass of 980 kg in a building where each floor is 3.6 m apart. If the elevator's power rating is 55 kW how long does it take for a trip from the 4th floor to the 8th?

2.51seconds

Explanation: Given that,

Mass = 980kg, Power = 55kw = 55000w, height = 4*3.6 = 14.4m g = 9.8m/s^2, time=?

Energy consumed = mass*g*height

Energy consumed = 980*9.8*14.4

Energy consumed = 138297.6joules

Where power = Energy consumed/time

55000 = 138297.6joules: time

55000t = 138297.6

t = 138297.6:55000

t = 2.51seconds

The time to complete the trip from the 4th to 8th floor is 2.51seconds