Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Since the change in kinetic energy is still zero, this means that the positive change in potential gravitational energy is equal to the negative of the change in internal energy. Let’s say you have a mass of 75 kilograms (165 pounds). This means that going up 1 meter would reduce your internal energy by 735 joules. This is called training.
Climbing the stairs against a staircase
Now we can return to the initial question: what does the principle of working energy say on the stairs compared to a staircase machine? Well, we have already done the physics of the stairs. It’s the same calculation if you go up to a 1 meter table or mount 100 stories – it’s just a different value for height. But suppose you stay in the same place while the stairs move under you. If someone measures your movement forward, it would say that your speed is zero. Your size does not change either, so now the work energy equation looks like this:
That said, the internal energy change is also zero, which means that you do not burn any calories. I mean, it can’t be true … right? So how to fix this? I will use a fine example based on This Steve Muggle video. This happens like this: imagine that you are climbing a moving escalator downwards. Again, an observer on the ground would see you as a stationary. However, we could also measure your speed from the reference frame of the escalator, and you would rise.
In fact, if the escalator had walls and a ceiling, you could not say that you stay in place. You wouldn’t even know that the stairs move. Since the stairs move at a constant speed (zero acceleration), it would be an inertial reference framework. In physics, any inertial reference framework is as valid as any other reference framework – the basic laws of physics remain the same. Therefore, from the point of view of the executive of the escalator, you are Raise and do work. It is the same as if you gave up a stationary framework.
But in fact, the staircase is more difficult
I said that the staircase and the climbing stairs were the same, but they are not. In fact, climbing 100 floors is easier than the equivalent distance on a staircase. Does it seem crazy? It’s a bit crazy. The reason they are different is that the gravitational field (g) is never really constant.
Remember that we have defined the potential gravitational energy as U = MXGXY? It’s not really bad, but it’s a bit misleading. In fact, the gravitational potential energy for the terrestrial person’s system would be defined as the following:
