the pendulum looses energy (work) on each swing because the bob returns to a lower height each time
when the bob stops (at rest, at the lowest point), the total lost energy (negative work) is equal to the difference in potential energy between the starting point and the lowest point ... m g h
A 2.20 kg pendulum starts from a height of 5.00m. It swings back and forth through one whole oscillation but only returns to a maximum height of 4.75m. After a long time the pendulum eventually winds down and comes to a stop. How much total negative work was done on the pendulum to bring it to rest at its lowest point?
I know that negative work during the first oscillation is 5.39 J.
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