Why are we more energetic when we ascend to the peak of mountain?
Because we gain gravitational potential energy.
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This invited several responses when I posted on Facebook, ranging from failure to consider kinetic energy and conservative field (which I had to add assumption that you travel on transport to the mountain), to the “exhaustion that saps our energy”. I guess this is the beauty of joke: if you don’t contemplate analytically, you will only laugh and do nothing else.
anzoteh96 