Before I risk making a fool of myself, here is a question to you physics professors and competent wannabes about the mathematical nature of energy:
Energy is always a scalar size, never a vector size - right? Direction plays no role when discussing what energy as such can and cannot do, right?
So even if the motion or force that gives rise to some form of energy (velocity for kinetic energy; gravity etc. for potential energies) are vector sizes, the energy itself is not? I read that it is calculated often as the scalar product of two vectors.
Correct?
Same is true for work - right?
The background to this question is the following interview - I am starting the transcript at the 9:50 mark. They are talking about the collapses of the World Trade Center towers, and how some of the heavy steel was hurled as far as 600 feet away from the building footprints. The interviewer had just talked about another guy and is relating what this guy said. The man answering is a professor of physics with a stellar publishing record (Hirsch-index = 52, if you know and care what that is):
http://ift.tt/1EEgOz0
Energy is always a scalar size, never a vector size - right? Direction plays no role when discussing what energy as such can and cannot do, right?
So even if the motion or force that gives rise to some form of energy (velocity for kinetic energy; gravity etc. for potential energies) are vector sizes, the energy itself is not? I read that it is calculated often as the scalar product of two vectors.
Correct?
Same is true for work - right?
The background to this question is the following interview - I am starting the transcript at the 9:50 mark. They are talking about the collapses of the World Trade Center towers, and how some of the heavy steel was hurled as far as 600 feet away from the building footprints. The interviewer had just talked about another guy and is relating what this guy said. The man answering is a professor of physics with a stellar publishing record (Hirsch-index = 52, if you know and care what that is):
http://ift.tt/1EEgOz0
Quote:
Interviewer: And when I pointed out this very issue, "why do we see things blasted upwards and outwards, how can gravity be doing that", his response was: "Well, you know, things bounce, and there was a tremendous amount of energy, gravitational energy, unleashed when these buildings came down, and with that much energy unleashed, just about anything could happen." How would you reply to him? Physics professor: The energy is vector, is directed downwards, and you could maybe have some angular thing to drive it out to the side, but it wouldn't go very far, it would keep accelerating downward. |
via International Skeptics Forum http://ift.tt/1Mr5zjj
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