Students had to do manual labor in order to have an intuitive understanding of work and energy.
Lab Part 1:
Students would hang weights from a balcony with a pulley system and calculate the time it takes them to pull the weights to the top of the balcony.
Balcony Pulley System:
First the students had to measure the height of the balcony.
There were stairs leading to the balcony so the students measured the height a single stair step and counted the number of steps.
They used that to calculate the height of the balcony.
The students then picked one of three masses, from 5 to 9 kg. And were timed on how fast they could pull the weight up to the height.
The height of the balcony was 4.29 meters. The mass of the object x gravity x the height of the balcony would equal the energy needed to move the object to the top of the balcony.
This divided by the time it took to move the object would provide the students power output.
The student calculated his energy and power output as such:
Energy
(5kg)(9.8m/s^2)(4.29m) = 210.21 joules
Power
210.21 joules / 10.49 seconds = 20.04 watts
Lab part 2
The students would record the energy and power it would take them to walk up and down the stairs at a constant speed. The students recorded the time it took for them to walk up and down the stairs. The students then used the same method as in part 1 to calculate Energy and Power.
Energy
(50kg)(9.8m/s^2)(4.29m) = 2102.1 joules
Power
2102.1 joules/ 14.5 seconds = 145 watts (walking up)
2102.1 joules/ 7.25 seconds = 290 watts (walking down)
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