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Flat.Uphill?
Bingo! Not everybody sees it that way.Well. The heavier person puts more stress, and possibly their muscles did more work to move the weight 3 miles. So, the heavier person burned more calories than the lighter person for the same distance at the same pace. but the lighter person may well just jog the 3 miles and burn the same amount of calories.
Who? Who doesn't see it that way? More weight over the same distance in the same period of time takes more energy/effort to accomplish. That's middle school stuff.Bingo! Not everybody sees it that way.
Seems screechingly obvious.Bingo! Not everybody sees it that way.
In your analogy, the large dozer should be moving 10 cubic yards of gravel while the small moves 5.Let's get Physics'ical.
View attachment 1811750
If a large dozer pushes a 5 cubic yards of gravel a distance 25 feet, and then a small dozer moves the 5 cubic yards of gravel back to the original position....
...the same amount of work was accomplished. The size of the vehicle, nor amount of fuel used, is factored into the work.
Maybe the original question was relating to thermal transfer?
It might have been more of...Let's get Physics'ical.
View attachment 1811752
If a large dozer pushes a 5 cubic yards of gravel a distance 25 feet, and then a small dozer moves the 5 cubic yards of gravel back to the original position....
...the same amount of work was accomplished. The size of the vehicle, nor amount of fuel used, is factored into the work.
Maybe the original question was relating to thermal transfer?
The operator of the large dozer noticed the pyrometer was indicating a higher than normal exhaust temperature, so he was using half throttle while pushing 5 cubic yards of gravel.In your analogy, the large dozer should be moving 10 cubic yards of gravel while the small moves 5.
If burning fuel is the purpose, then it would be considered work.It might have been more of...
Did both persons, walking same pace, for the same distance, burn the same amount of calories, if one person is twice as large as the other person?
Edit a better analogy. Stick two identical 200hp engines and identical transmissions in two vehicles, one is a 2,000lb car, the other a 4,000lb van.. which engine burned more fuel to go the same distance?
Work = Mass moved a given distance.State your assumptions; are we talking work in the physics sense or work in the practical sense? Your assumptions define the answer.
In the physics sense the weight of the gravel and the wight of the dozer counts (or in the original question the weight of the person). So a bigger dozer does more work since it is moving more mass (weigh of dozer + weight of gravel) and similarly the bigger person is doing more work to move the mass of their body.
However in a practical sense we only care about the gravel, not the device being used to push it. We divide up the problem into work and efficiency. The gravel defines the amount of work that is done (the same in both cases) while the machine used to move it defines the efficiency that it gets done with (in one or some of many dimensions; fuel consumption, time taken, total cost to do the job, etc.). In that sense the two people walking did the same amount of work (they went to the same destination in the same amount of time).
If you do not define the parameters of your problem then you leave it open to interpretation, and then there is no right answer. If you claim there is then the game we are playing is not actually "what is the correct answer" it is "guess what assumptions I made that allows me to conclude my answer is correct."
Problem space definition is a key aspect of problem solving. If you cannot narrowly define your specifications then any number of conclusions are possible. If you need a specific answer then you need a specific problem space. The more specific the answer needs to be the more specific the problem definition needs to be.