Hi. Again.

A ship navigates against the river current, its engine developing 1000 horsepower and is not enough, advancing nothing, just maintaining position.

Another identical ship next to it also maintains position as it is anchored. How many horsepower is the anchor developing ? 🙄

Zero.

Work is force (dot) displacement. No displacement, no work. No work, no power.

4 hours ago, Externet said:

Hi. Again.

A ship navigates against the river current, its engine developing 1000 horsepower and is not enough, advancing nothing, just maintaining position.

Another identical ship next to it also maintains position as it is anchored. How many horsepower is the anchor developing ? 🙄

To add a bit to @swansont ’s reply, both ships dissipate (as heat) energy at the same rate, due to the motion of their hulls relative to the water. . However in the case of the moored ship this energy comes from the current.