posted by stephanie .
What is the average useful power output of a person who does 5.50×106 J of useful work in 6.50 h?
235 W correct answer
Working at this rate, how long will it take this person to lift 1850 kg of bricks 1.20 m to a platform? (Work done to lift his body can be omitted because it is not considered useful output here.)
92.6 s correct
can someone give me the steps to achieve these answers?
6.5 h * 3600 s/h = 23400 seconds
5.5 * 10^6/2.34*10^4 watts
work done = m g h = 1850*9.81*1.2
power = work/time
235 = work/time
time = work/235