9 An escalator carries 60 people of average mass 70 kg to
a height of 5 m in one minute. Find the power needed
to do this.
First, we need to calculate the total work done in lifting 60 people to a height of 5 m:
Work = force x distance
Work = mass x gravity x height
Work = (60 x 70) x 9.8 x 5
Work = 33,600 J
Next, we need to calculate the power needed to do this work in one minute:
Power = Work / time
Power = 33,600 J / 60 s
Power = 560 W
Therefore, the power needed to lift 60 people to a height of 5 m in one minute is 560 watts.