- You have a mass of 75 kilograms. You walk up a 5 meter flight of stairs in 32 seconds. a) how much work have you done?
b) how many watts of power have you produced?
c) how many horsepower have you produced?

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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asthenosphere and convection

scientific laws are the result of testing theories and proving them to be facts.