Question

If we push a wall for a longtime, no work is done but we get tired.

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Answer 1

He said that muscles under tension, or compression actually consume energy by metabolizing ATP, the chemical energy carrier in the body. ... Although you are doing no work on the wall, you are still eating up ATP energy by keeping your muscles clenched. Eventually you get tired.

Answer 2

Answer:

That is so because the amount of force exerted by us to push the wall tires us. Hence, we get exhausted without doing any work.