Physical problems: I lift a heavy object with both hands and stand still, so I don't do any work, but I will be very tired. Where is the energy consumption?

1. The work calculated according to the formula w (work) =F (force) XS (displacement) is mechanical work. So although you haven't moved for a long time, you haven't done any mechanical work, which is beyond doubt.

Besides mechanical work, there are many kinds of jobs.

In this case, the main consumption is chemical work. Because you lift a heavy object, your muscles are tense, which leads to the acceleration of biochemical reactions in the human body, and at the same time accelerates the consumption of energy-this is mainly biochemical reactions, even anaerobic breathing, which is manifested as muscle soreness and sweating. At this time, the direction of energy change is mainly that biochemical energy becomes internal energy.