John applied 20N of force to a bag of dog food while walking up a 6.0 m flight of stairs

force

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John applied 20N of force to a bag of dog food while walking up a 6.0 m flight of stairs. How much work was done on the bag?

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You push down on a 3.0 N box for 10 minutes. How much work was done?

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Answer:

a) work = force.displacement = 20 x 6 = 120 J.

b) You did not move the box, the displacement was zero. Hence the work done is 0 J.