How do you calcuate total distance, work and power ?

Question

The height of one step is 18.5 cm and there are 10 steps. I ran twice. (up and down, up and down) So do you do 18.5 X 20=370 cm.? might be correct but not sure... My weight in pounds is 140, in kg it is 63 and in newtons it is 190.4 to find work----- to find work,(W=fxd) do you multiply 190.4X0.37 I converted the 370 into meters because work is measure in Newtons meter Joules. How do you find power? (p=w/t) My time was 16.79.....will it be 140/16.79?

Answer 1

If you ran up-down-up-down in theory you have done no work since your energy level at the end of the runs is the same as the beginning. Whatever work is done is due to other forces (friction, air resistance, etc.) and non-reversible process (you can't take back the energy on the way down like a rolling ball might). You have no information about what those other factors are.

However, you are correct about work = force times distance (for a constant force). So the work going up the steps is weight x height (weight is a force = mass * g). If you measure your weight on a scale that reads kg, you are really reading newtons.

Power is work divided by time; you would have to know how long it took to climb the stairs to calculate the (average) power.