3 ms·

Friction. Work isn't just about height.

• thfuran 5mo ago
  Holding that block stationary at arms length then. 0 work.
  • dotancohen 5mo ago
    Put that block on a shelf at the same height. 0 work. The fact that your muscles burn ATP just fighting gravity is a feature of biology, not fundamental to the physics involved. If you want to read about another similar example, Google for rocket launch gravity losses.
    • thfuran 5mo ago
      I think you're missing the point. A lot of basic mechanics actually isn't especially intuitive because things like work simply do not map well to everyday experience. I'm not suggesting that work is defined incorrectly or something.
      • dotancohen 4mo ago
        I see what you're saying now, and I agree.