In my high school physics class, we are doing an experiment where we go up a flight of steps, record the time it takes, and calculate the work done in the vertical direction. I understand everything (I am a pretty bright student) except one part that I simply cannot wrap my head around. To calculate work, we use W = Fd, and to get F we use F = mg, finding our weight. I don't understand how we are moving upward if our normal force is equal to our weight. Isn't each person's normal force equal to their weight when they are just standing up without moving? My teacher tried to explain it to me, and he said that our normal force is greater than our weight when we jump, which would be an upward velocity. When we climb stairs we have an upward velocity, so how can the normal force be equal to our weight? Thank you for helping!